"""Tool-call execution: sequential and concurrent dispatch, extracted from AIAgent.

Functions take the parent ``AIAgent`` first; ``run_agent`` keeps thin wrappers, and
tests that patch ``run_agent._set_interrupt`` still work because we reach it via ``_ra()``.
"""

from __future__ import annotations

import concurrent.futures
import contextlib
import json
from pathlib import Path
import logging
import os
import random
import threading
import time
from dataclasses import dataclass
from typing import Any, Callable, Optional

from agent.display import (
    KawaiiSpinner,
    build_tool_preview as _build_tool_preview,
    build_tool_label as _build_tool_label,
    get_cute_tool_message as _get_cute_tool_message_impl,
    get_tool_emoji as _get_tool_emoji,
    redact_tool_args_for_display as _redact_tool_args_for_display,
    _detect_tool_failure,
)
from agent.message_sanitization import coalesce_tool_call_id
from agent.inline_tool_executors import (
    INLINE_TOOL_EXECUTORS,
    InlineToolContext,
    emit_terminal_post_tool_call,
    tool_hook_ids,
)
from agent.tool_dispatch_helpers import (
    _NEVER_PARALLEL_TOOLS,
    _is_destructive_command,
    _is_multimodal_tool_result,
    _multimodal_text_summary,
    _append_subdir_hint_to_multimodal,
    _plan_tool_batch_segments,
    make_tool_result_message,
)
from tools.terminal_tool import (
    get_active_env,
)
from tools.thread_context import propagate_context_to_thread
from tools.tool_result_storage import (
    maybe_persist_tool_result,
    enforce_turn_budget,
    extract_persisted_path,
)
from tools.budget_config import BudgetConfig, DEFAULT_BUDGET, budget_for_context_window

logger = logging.getLogger(__name__)


def _pairing_tool_call_id(tool_call: Any) -> str:
    """Return the canonical id used by the persisted assistant message."""
    return coalesce_tool_call_id(tool_call)


def _tc_name(tool_call: Any) -> str:
    return getattr(getattr(tool_call, "function", None), "name", "") or "tool"


def _record_persisted_path_for_stub(agent, tool_call_id: str, function_result) -> None:
    """Record the spillover file path so a later result-reference stub can't dangle (best-effort)."""
    try:
        if not isinstance(function_result, str):
            return
        path = extract_persisted_path(function_result)
        if path:
            agent._tool_guardrails.record_persisted_result(tool_call_id, path)
    except Exception as exc:
        logger.debug("persisted-path record for result stub failed: %s", exc)


def _ensure_file_checkpoint(agent, function_name: str, function_args: dict, effective_task_id: str) -> None:
    """Checkpoint the same workspace path that the file tool will mutate."""
    file_path = function_args.get("path", "")
    if not file_path:
        return
    # File tools resolve relative paths against the task's live cwd (differs from the
    # process cwd in Docker); resolve the same way before locating the project root.
    from tools.file_tools import _resolve_path_for_task

    resolved_path = _resolve_path_for_task(file_path, effective_task_id or "default")
    work_dir = agent._checkpoint_mgr.get_working_dir_for_path(str(resolved_path))
    agent._checkpoint_mgr.ensure_checkpoint(work_dir, f"before {function_name}")


def _budget_for_agent(agent) -> BudgetConfig:
    """Tool-result BudgetConfig scaled to the agent's context window (default when unknown)."""
    try:
        ctx = getattr(getattr(agent, "context_compressor", None), "context_length", None)
        # budget_for_context_window(None), not DEFAULT_BUDGET, so the MCP threshold
        # override still applies when the context length isn't resolvable.
        return budget_for_context_window(int(ctx) if ctx else None)
    except Exception:
        return DEFAULT_BUDGET

# Maximum number of concurrent worker threads for parallel tool execution.
_MAX_TOOL_WORKERS = 8
_DEFAULT_IMAGE_PARALLEL_REQUESTS = 4
# Generous ceiling for slow-but-valid tool work so the batch guard never preempts a legitimate attempt.
_DEFAULT_CONCURRENT_TOOL_TIMEOUT_S = 420.0
# Start-order gate wait: long enough for an approval round-trip, short enough that one
# wedged dispatch cannot starve the batch.
_START_ORDER_GATE_TIMEOUT_S = 120.0
# Fallback authorization-gate lock bound; the effective bound derives from approvals.timeout
# (see _authorization_gate_lock_timeout) since overstaying it means wedged.
_AUTHORIZATION_GATE_LOCK_TIMEOUT_S = 360.0


def _authorization_gate_lock_timeout() -> float:
    """Bound for the authorization serialization lock: approval timeout + margin.

    Delegates to ``tools.approval.human_wait_ceiling`` so the two bounds can't drift: never
    break serialization while an approval prompt is answerable, never let a wedged holder
    park other workers forever. Safety-capped so a huge approvals.timeout can't overflow
    Lock.acquire; deliberately NOT min()'d with the fallback so the gate never gives up early.
    """
    try:
        from tools.approval import human_wait_ceiling

        return human_wait_ceiling()
    except Exception:
        return _AUTHORIZATION_GATE_LOCK_TIMEOUT_S


class _BatchAbandoned(BaseException):
    """Raised inside a worker when the batch was abandoned before dispatch.

    BaseException so ``except Exception`` handlers in the middleware chain can't swallow it.
    """


def _parse_tool_arguments(raw_arguments: Any) -> tuple[dict, Optional[str]]:
    """Parse model-emitted arguments without repairing or coercing them."""
    try:
        arguments = json.loads(raw_arguments)
    except (json.JSONDecodeError, TypeError):
        arguments = None
    if isinstance(arguments, dict):
        return arguments, None
    return {}, json.dumps(
        {
            "error": "Invalid tool arguments",
            "message": (
                "Tool arguments must be a valid JSON object; tool was not executed."
            ),
        },
        ensure_ascii=False,
    )


def _resolve_concurrent_tool_timeout() -> float | None:
    """Per-batch concurrent deadline: ``timeouts.tools.concurrent_batch`` wins,
    ``HERMES_CONCURRENT_TOOL_TIMEOUT_S`` is the legacy bridge, ``0``/negative disables."""
    from agent.deadline import resolve_timeout

    return resolve_timeout(
        "tools.concurrent_batch",
        default=_DEFAULT_CONCURRENT_TOOL_TIMEOUT_S,
        env_var="HERMES_CONCURRENT_TOOL_TIMEOUT_S",
    )


def _flush_session_db_after_tool_progress(agent, messages: list, *, stage: str) -> bool:
    """Flush tool-call progress to the session DB before projecting it to any UI.

    Tool side effects can kill/restart the process before turn-end persistence runs.
    """
    try:
        persisted = agent._flush_messages_to_session_db(messages) is not False
        if not persisted:
            agent._incremental_persistence_failed = True
            # Flush recorded any classified cause at the catch site; only default
            # to 'unknown' when nothing more specific exists.
            if getattr(agent, "_last_persistence_error_cause", None) is None:
                agent._last_persistence_error_cause = "unknown"
        return persisted
    except Exception as exc:
        agent._incremental_persistence_failed = True
        from hermes_state import classify_persistence_error
        agent._last_persistence_error_cause = classify_persistence_error(exc)
        logger.warning("Incremental tool-call persistence failed after %s: %s", stage, exc)
        return False


def _image_generate_parallel_limit() -> int:
    """Configured image-generation parallelism cap (conservative default; backend bursts
    hit TTFB/rate-limit failures)."""
    try:
        from hermes_cli.config import load_config

        cfg = load_config() or {}
        image_gen = cfg.get("image_gen") if isinstance(cfg, dict) else None
        value = image_gen.get("max_parallel_requests") if isinstance(image_gen, dict) else None
    except Exception:
        value = None

    try:
        limit = int(value)
    except (TypeError, ValueError):
        limit = _DEFAULT_IMAGE_PARALLEL_REQUESTS
    return max(1, min(limit, _MAX_TOOL_WORKERS))


def _max_workers_for_tool_batch(runnable_calls) -> int:
    """Return the worker cap for a concurrent tool batch."""
    if not runnable_calls:
        return 0
    max_workers = _MAX_TOOL_WORKERS
    if any((call[2] if len(call) >= 3 else None) == "image_generate" for call in runnable_calls):
        max_workers = min(max_workers, _image_generate_parallel_limit())
    return min(len(runnable_calls), max_workers)


def _ra():
    """Lazy reference to ``run_agent`` so patches like ``run_agent._set_interrupt`` work."""
    import run_agent
    return run_agent


def _is_interpreter_shutdown_submit_error(exc: RuntimeError) -> bool:
    """Shutdown-race predicate; ``tools.interpreter_shutdown`` knows both CPython message variants."""
    from tools.interpreter_shutdown import interpreter_shutting_down

    return interpreter_shutting_down(exc)


_emit_terminal_post_tool_call = emit_terminal_post_tool_call


@dataclass
class _ToolCallRef:
    """Identity of one tool call as every hook / result message sees it: the (possibly
    middleware-rewritten) name and args, the task, the pairing id and the request trace."""

    name: str
    args: dict
    task_id: str
    call_id: str
    trace: list

    def emit_post(self, agent, result, *, trace=None, **outcome) -> None:
        """Emit the one terminal ``post_tool_call`` for this call (``outcome`` = status /
        error_type / error_message / duration_ms). Resolved through the module attribute so
        tests patching ``_emit_terminal_post_tool_call`` still intercept."""
        _emit_terminal_post_tool_call(
            agent,
            function_name=self.name,
            function_args=self.args,
            result=result,
            effective_task_id=self.task_id,
            tool_call_id=self.call_id,
            middleware_trace=list(self.trace if trace is None else trace),
            **outcome,
        )

    def emit_cancelled(self, agent, start_time: float) -> str:
        """Synthesize the ``cancelled`` result for a KeyboardInterrupt mid-tool and emit its hook."""
        result = json.dumps(
            {"error": "Tool execution cancelled by user interrupt", "status": "cancelled"},
            ensure_ascii=False,
        )
        self.emit_post(
            agent, result,
            duration_ms=int((time.time() - start_time) * 1000),
            status="cancelled",
            error_type="keyboard_interrupt",
            error_message="Tool execution cancelled by user interrupt",
        )
        return result

    def emit_invalid_arguments(self, agent, result: str) -> None:
        self.emit_post(
            agent, result, trace=[],
            status="error", error_type="invalid_tool_arguments",
            error_message="Tool arguments must be a valid JSON object",
        )


def _append_skipped_tool_results(
    agent,
    messages: list,
    tool_calls,
    effective_task_id: str,
    *,
    content: str,
    hook_error_type: Optional[str] = None,
    hook_id: Optional[Callable[[Any], str]] = None,
    flush_stage: Optional[str] = None,
    stop_on_flush_failure: bool = True,
) -> bool:
    """Append one ``tool`` result per unstarted call so the assistant tool-call turn never
    lacks matching results (role-alternation violation).

    ``content`` is formatted with ``{name}``. ``hook_error_type`` also emits the terminal
    ``post_tool_call`` (status=cancelled) per call, ``hook_id`` overriding the hook's id.
    ``flush_stage`` flushes the session DB after each append; returns False on the first
    failed flush when ``stop_on_flush_failure`` (the caller must stop the batch).
    """
    for tc in tool_calls:
        name = _tc_name(tc)
        result = content.format(name=name)
        messages.append(make_tool_result_message(name, result, _pairing_tool_call_id(tc), effect_disposition="none"))
        if hook_error_type is not None:
            _ToolCallRef(name, {}, effective_task_id, (hook_id or _pairing_tool_call_id)(tc), []).emit_post(
                agent, result,
                status="cancelled", error_type=hook_error_type, error_message="Tool execution skipped due to user interrupt",
            )
        if flush_stage is not None:
            flushed = _flush_session_db_after_tool_progress(agent, messages, stage=f"{flush_stage} {name}")
            if not flushed and stop_on_flush_failure:
                return False
    return True


def _tool_search_scoped_names(agent) -> frozenset:
    """Deferrable tool names the session may invoke via ``tool_call``.

    The Tool Search unwrap bypasses the bridge's scope check in
    ``model_tools.handle_function_call``, so restricted sessions are validated against
    this set. Cached on the agent; refreshed when the registry generation changes.
    """
    try:
        import model_tools
        from tools import tool_search as _ts
        from tools.registry import registry as _registry
    except Exception:
        return frozenset()

    enabled = getattr(agent, "enabled_toolsets", None)
    disabled = getattr(agent, "disabled_toolsets", None)
    cache_key = (
        _registry.current_scope_key(),
        getattr(_registry, "_generation", 0),
        frozenset(enabled) if enabled is not None else None,
        frozenset(disabled) if disabled is not None else None,
    )
    cached = getattr(agent, "_tool_search_scope_cache", None)
    if cached is not None and cached[0] == cache_key:
        return cached[1]
    try:
        scoped_defs = model_tools.get_tool_definitions(
            enabled_toolsets=enabled,
            disabled_toolsets=disabled,
            quiet_mode=True,
            skip_tool_search_assembly=True,
        ) or []
        names = _ts.scoped_deferrable_names(scoped_defs)
    except Exception:
        names = frozenset()
    try:
        agent._tool_search_scope_cache = (cache_key, names)
    except Exception:
        pass
    return names


def _canonical_tool_name(function_name: str) -> str:
    """Map legacy tool-name aliases BEFORE agent-loop dispatch."""
    from model_tools import _LEGACY_TOOL_ALIASES as _lta

    return _lta.get(function_name, function_name)


def _unwrap_tool_search_call(
    agent, function_name: str, function_args: dict, *, flatten_probe: bool = False
) -> tuple[str, dict, Optional[str]]:
    """Peel the ``tool_call`` bridge so downstream hooks see the underlying tool.

    Checkpointing, guardrails, plugin hooks and the activity feed must observe the real
    tool name, not the bridge. ``tool_call.function`` stays untouched for the transcript
    and tool_call_id pairing. The unwrap bypasses handle_function_call's scope check, so
    session toolset scope is enforced HERE. Returns ``(name, args, scope_block)``;
    ``scope_block`` is the block message when the underlying tool is out of scope or its
    args fail the deferred-schema probe (``flatten_probe`` collapses the probe's JSON
    payload to one plain string for callers that wrap the message in ``{"error": ...}``).
    """
    scope_block: Optional[str] = None
    try:
        from tools import tool_search as _ts
        if function_name == _ts.TOOL_CALL_NAME:
            underlying, underlying_args, err = _ts.resolve_underlying_call(function_args)
            if not err and underlying:
                if underlying in _tool_search_scoped_names(agent):
                    # Validate before unwrapping: the generic bridge hides the concrete
                    # parameter schema from provider-native tool-call validation.
                    probe_err = _ts.validate_deferred_call_args(underlying, underlying_args)
                    if probe_err is None:
                        return underlying, underlying_args, None
                    scope_block = probe_err
                    if flatten_probe:
                        try:
                            probe = json.loads(probe_err)
                            scope_block = (
                                f"{probe.get('error', '')} Parameters schema: "
                                f"{json.dumps(probe.get('parameters', {}), ensure_ascii=False)}. "
                                f"{probe.get('hint', '')}"
                            ).strip()
                        except Exception:
                            scope_block = probe_err
                else:
                    scope_block = (
                        f"'{underlying}' is not available in this session. "
                        "Use tool_search to find tools you can call."
                    )
    except Exception:
        pass
    return function_name, function_args, scope_block


@dataclass
class _ParsedCall:
    """One model tool call after alias canonicalization, arg parsing and bridge unwrap."""

    tool_call: Any
    name: str
    args: dict
    middleware_trace: list
    parse_error: Optional[str]
    scope_block: Optional[str]

    def ref(self, task_id: str) -> _ToolCallRef:
        return _ToolCallRef(self.name, self.args, task_id, _pairing_tool_call_id(self.tool_call), self.middleware_trace)


def _parse_tool_call(agent, tool_call, *, flatten_probe: bool = False) -> _ParsedCall:
    name = _canonical_tool_name(tool_call.function.name)
    args, parse_error = _parse_tool_arguments(tool_call.function.arguments)
    if parse_error is not None:
        return _ParsedCall(tool_call, name, args, [], parse_error, None)
    name, args, scope_block = _unwrap_tool_search_call(agent, name, args, flatten_probe=flatten_probe)
    return _ParsedCall(tool_call, name, args, [], None, scope_block)


@dataclass
class _ManagedToolResult:
    result: Any
    args: dict[str, Any]
    middleware_trace: list[dict[str, Any]]
    blocked: bool
    dispatched: bool


class _ToolTimeoutResult(str):
    """Marker for a synthesized sequential-tool timeout result."""


class _ToolCancelledResult(str):
    """Marker for a synthesized sequential-tool user-interrupt result.

    The terminal post_tool_call event was already emitted (status=cancelled), so a
    late-finishing abandoned worker must not report success.
    """


class _ConcurrentToolAuthorizationGate:
    """Serialize policy prompts and exclude human approval waits from batch deadlines.

    The acquire is BOUNDED: on expiry the worker prompts unserialized rather than
    starving the batch behind a wedged plugin/approval client.

    Deadline exclusion is measured at the SOURCE of the human wait
    (``tools.approval.human_wait_seconds``), NOT as gate residency: residency-based
    exclusion let a wedged plugin keep the deadline from ever firing.
    """

    def __init__(self, *, lock_timeout: float | None = None, session_key: str | None = None) -> None:
        self._serialization_lock = threading.Lock()
        self._lock_timeout = _authorization_gate_lock_timeout() if lock_timeout is None else lock_timeout
        self._session_key = session_key
        if self._session_key is None:
            try:
                from tools.approval import get_current_session_key

                # Snapshot on the SUBMITTING thread: excluded_seconds() is polled
                # from the batch wait loop, whose context may differ from workers'.
                self._session_key = get_current_session_key()
            except Exception:
                logger.debug(
                    "authorization gate could not snapshot the session key; "
                    "human-wait exclusion will re-resolve it at poll time",
                    exc_info=True,
                )
        self._baseline_wait_seconds = self._human_wait_seconds()

    def _human_wait_seconds(self) -> float:
        try:
            from tools.approval import human_wait_seconds

            return human_wait_seconds(self._session_key)
        except Exception:
            return 0.0

    def run(self, callback):
        acquired = self._serialization_lock.acquire(timeout=self._lock_timeout)
        if not acquired:
            logger.warning(
                "authorization gate lock not acquired after %.1fs "
                "(holder wedged in a pre_tool_call plugin or approval "
                "round-trip?); running prompt unserialized",
                self._lock_timeout,
            )
            return callback()
        try:
            return callback()
        finally:
            self._serialization_lock.release()

    def excluded_seconds(self) -> float:
        """Return human-approval wait seconds accrued since the batch started."""
        return max(0.0, self._human_wait_seconds() - self._baseline_wait_seconds)


@contextlib.contextmanager
def _registered_tool_worker(agent):
    """Track this worker tid for interrupt fan-out (``AIAgent.interrupt()``).

    On exit (including BaseException, which bypasses ``except Exception``) the tid is
    discarded and its interrupt bit cleared so a recycled tid starts clean.
    """
    tid = threading.current_thread().ident
    with agent._tool_worker_threads_lock:
        agent._tool_worker_threads.add(tid)
    try:
        yield tid
    finally:
        with agent._tool_worker_threads_lock:
            agent._tool_worker_threads.discard(tid)
        try:
            _ra()._set_interrupt(False, tid)
        except Exception:
            pass


_NO_REASON = object()


def _interrupt_worker_tids(agent, tids, *, reason=_NO_REASON) -> None:
    """Raise the interrupt bit on each worker tid (best-effort, via ``run_agent``)."""
    kwargs = {} if reason is _NO_REASON else {"reason": reason}
    for tid in tids:
        try:
            _ra()._set_interrupt(True, tid, **kwargs)
        except Exception:
            pass


def _set_worker_activity_callback(agent) -> None:
    """The activity callback is thread-local: bind it on THIS thread so tool-layer heartbeats fire."""
    try:
        from tools.environments.base import set_activity_callback

        set_activity_callback(agent._touch_activity)
    except Exception:
        pass


# Heartbeat cadence; must stay far below the gateway turn-inactivity timeout
# (default 1800s) so a silent-but-healthy tool never looks idle.
_TOOL_ACTIVITY_HEARTBEAT_INTERVAL_S = 30.0


def _run_tool_activity_heartbeat(
    agent,
    stop_event: threading.Event,
    label: str,
    interval: float = _TOOL_ACTIVITY_HEARTBEAT_INTERVAL_S,
) -> None:
    """Daemon thread stamping ``agent._touch_activity`` every ``interval`` seconds until
    ``stop_event`` is set, so the gateway inactivity watchdog never abandons a turn whose
    tool runs silently. Wedged tools stay bounded by the tool layer's own timeouts."""
    try:
        while not stop_event.wait(interval):
            agent._touch_activity(label)
    except Exception:
        # A heartbeat must never break the agent loop.
        pass


def _run_with_activity_heartbeat(agent, function_name: str, fn):
    """Run ``fn()`` under the activity heartbeat; covers both executor paths."""
    stop = threading.Event()
    thread = threading.Thread(
        target=_run_tool_activity_heartbeat,
        args=(agent, stop, f"tool running: {function_name}"),
        kwargs={"interval": _TOOL_ACTIVITY_HEARTBEAT_INTERVAL_S},
        daemon=True,
        name=f"tool-activity-hb-{function_name[:24]}",
    )
    thread.start()
    try:
        return fn()
    finally:
        stop.set()
        thread.join(timeout=2.0)


def _blocked_tool_result(agent, ref: _ToolCallRef, *, block_message: Optional[str], block_error_type: str, guardrail_decision) -> str:
    """Synthesize the result for a call blocked by scope/plugin (``block_message``) or by
    guardrail policy (``guardrail_decision``) and emit its terminal post_tool_call."""
    if block_message is not None:
        result = json.dumps({"error": block_message}, ensure_ascii=False)
        error_type = block_error_type
        error_message = block_message
    else:
        result = agent._guardrail_block_result(guardrail_decision)
        error_type = "guardrail_block"
        error_message = getattr(guardrail_decision, "message", None) or "Tool blocked by guardrail policy"
    ref.emit_post(agent, result, status="blocked", error_type=error_type, error_message=error_message)
    return result


def _pre_tool_block(agent, ref: _ToolCallRef):
    """Run ``pre_tool_call`` plugin hooks; returns ``(block_message, final_args)`` with any
    hook-modified args applied. Hook failures never block."""
    try:
        from hermes_cli.plugins import _dispatch_pre_tool_call_hooks

        block_msg, modified_args = _dispatch_pre_tool_call_hooks(
            ref.name,
            ref.args,
            **tool_hook_ids(agent, ref.task_id, ref.call_id),
            middleware_trace=list(ref.trace),
        )
        return block_msg, (ref.args if modified_args is None else modified_args)
    except Exception:
        return None, ref.args


def _dispatch_authorized_once(
    agent,
    state: _ManagedToolResult,
    ref: _ToolCallRef,
    *,
    execute,
    scope_block: str | None,
    display_index: int | None,
    begin_execution,
    authorization_gate: _ConcurrentToolAuthorizationGate | None,
) -> Any:
    """Hermes policy (scope → plugin pre-hooks → guardrails) then the one real dispatch.

    ``ref.args`` are the middleware-final args; plugin ``modify`` hooks may rewrite them
    (mirrored into ``state.args``). ``begin_execution`` (concurrent start-order gate) is
    advanced exactly once on every path so later-ordered workers keep moving; blocked
    calls advance it without a callback.
    """
    def _advance_start_order(callback=None) -> None:
        if begin_execution is not None:
            begin_execution(callback)
        elif callback is not None:
            callback()

    block_message, block_error_type = scope_block, "tool_scope_block"
    if block_message is None:
        block_error_type = "plugin_block"
        resolve = lambda: _pre_tool_block(agent, ref)  # noqa: E731
        block_message, ref.args = resolve() if authorization_gate is None else authorization_gate.run(resolve)
        state.args = ref.args

    guardrail_decision = None
    if block_message is None:
        guardrail_decision = agent._tool_guardrails.before_call(ref.name, ref.args)
        if guardrail_decision.allows_execution:
            guardrail_decision = None

    if block_message is not None or guardrail_decision is not None:
        _advance_start_order()
        state.blocked = True
        return _blocked_tool_result(
            agent, ref,
            block_message=block_message, block_error_type=block_error_type, guardrail_decision=guardrail_decision,
        )

    if ref.name == "memory":
        agent._turns_since_memory = 0
    elif ref.name == "skill_manage":
        agent._iters_since_skill = 0

    _advance_start_order(lambda: _begin_tool_execution(
        agent,
        function_name=ref.name,
        function_args=ref.args,
        effective_task_id=ref.task_id,
        tool_call_id=ref.call_id,
        display_index=display_index,
    ))
    return _run_with_activity_heartbeat(agent, ref.name, lambda: execute(ref.args))


def _run_agent_tool_execution_middleware(
    agent,
    *,
    function_name: str,
    function_args: dict,
    effective_task_id: str,
    tool_call_id: str,
    execute,
    scope_block: str | None = None,
    display_index: int | None = None,
    middleware_trace: list[dict[str, Any]] | None = None,
    begin_execution=None,
    authorization_gate: _ConcurrentToolAuthorizationGate | None = None,
) -> _ManagedToolResult:
    """Run Relay rewrites before Hermes policy and dispatch exactly once."""
    from agent import relay_tools
    from hermes_cli.middleware import (
        apply_tool_request_middleware,
        run_tool_execution_middleware,
    )

    trace = middleware_trace if middleware_trace is not None else []
    state = _ManagedToolResult(result=None, args=function_args, middleware_trace=trace, blocked=False, dispatched=False)
    dispatch_lock = threading.Lock()

    def _authorized_dispatch(final_args: dict[str, Any]) -> Any:
        with dispatch_lock:
            if state.dispatched:
                raise RuntimeError("Hermes tool execution callback invoked more than once")
            state.dispatched = True
            state.blocked = False
            state.args = final_args
        return _dispatch_authorized_once(
            agent,
            state,
            _ToolCallRef(function_name, final_args, effective_task_id, tool_call_id, trace),
            execute=execute,
            scope_block=scope_block,
            display_index=display_index,
            begin_execution=begin_execution,
            authorization_gate=authorization_gate,
        )

    def _hermes_pipeline(relay_args: dict[str, Any]) -> Any:
        request_result = apply_tool_request_middleware(
            function_name,
            relay_args,
            skip_relay=True,
            **tool_hook_ids(agent, effective_task_id, tool_call_id),
        )
        request_args = request_result.payload if isinstance(request_result.payload, dict) else relay_args
        trace.clear()
        trace.extend(request_result.trace)
        return run_tool_execution_middleware(
            function_name,
            request_args,
            lambda next_args: _authorized_dispatch(next_args if isinstance(next_args, dict) else request_args),
            original_args=function_args,
            **tool_hook_ids(agent, effective_task_id, tool_call_id),
        )

    state.result, _relay_args = relay_tools.execute(
        function_name,
        function_args,
        _hermes_pipeline,
        session_id=str(getattr(agent, "session_id", "") or ""),
        metadata={
            "task_id": effective_task_id or "",
            "turn_id": getattr(agent, "_current_turn_id", "") or "",
            "api_request_id": getattr(agent, "_current_api_request_id", "") or "",
            "tool_call_id": tool_call_id or "",
        },
    )
    return state


# Sequential wait-loop interrupt poll cadence: /stop lands within ~1s even when
# the tool never polls is_interrupted().
_SEQUENTIAL_INTERRUPT_POLL_SECONDS = 1.0


def _resolve_sequential_tool_timeout() -> float | None:
    """Deadline for one sequential tool call.

    ``timeouts.tools.sequential_call`` wins; unset inherits the concurrent batch deadline
    so the two paths can't drift. ``0``/negative disables the bound.

    Deliberately NOT ``agent.deadline.run_bounded_sync``: both executors extend their
    deadline while an approval prompt is open (MUST-preserve), which the fixed-deadline
    primitive can't express.
    """
    from agent.deadline import resolve_timeout

    return resolve_timeout("tools.sequential_call", default=_resolve_concurrent_tool_timeout())


def _abandoned_sequential_result(agent, ref: _ToolCallRef, message: str, result_cls, **outcome) -> _ManagedToolResult:
    """Emit the terminal post_tool_call for a worker the sequential runner gave up on
    (timeout / interrupt) and wrap ``message`` in its marker ``result_cls``."""
    ref.emit_post(agent, message, **outcome)
    return _ManagedToolResult(result=result_cls(message), args=ref.args, middleware_trace=ref.trace, blocked=False, dispatched=True)


def _poll_sequential_future(agent, future, function_name: str, deadline: float | None, started: float, authorization_gate) -> tuple[str, Any]:
    """Wait for the worker in interrupt-poll slices, extending the deadline by human
    approval wait. Returns ``("done", result)``, ``("timeout", None)`` or ``("interrupted", None)``.

    A disabled deadline still polls: this loop is what makes a non-cooperative tool
    interruptible, so no deadline must not mean no interrupt checks.
    """
    _last_heartbeat = 0
    while True:
        wait_slice = _SEQUENTIAL_INTERRUPT_POLL_SECONDS
        if deadline is not None:
            remaining = deadline + authorization_gate.excluded_seconds() - time.monotonic()
            if remaining <= 0:
                return "timeout", None
            wait_slice = min(wait_slice, remaining)
        try:
            return "done", future.result(timeout=wait_slice)
        except concurrent.futures.TimeoutError:
            if agent._interrupt_requested:
                return "interrupted", None
            elapsed = int(time.monotonic() - started)
            if elapsed - _last_heartbeat >= 30:
                _last_heartbeat = elapsed
                agent._touch_activity(f"sequential tool running ({elapsed}s): {function_name}")


def _run_sequential_tool_execution_middleware(
    agent,
    *,
    function_name: str,
    function_args: dict,
    effective_task_id: str,
    tool_call_id: str,
    execute,
    scope_block: str | None = None,
    display_index: int | None = None,
    middleware_trace: list[dict[str, Any]] | None = None,
) -> _ManagedToolResult:
    """Run one sequential call on a worker thread under the concurrent executor's deadline.

    Interactive tools (``clarify``) own their wait via ``agent.clarify_timeout``; the
    generic deadline would report ``tool_timeout`` while the prompt is still live.
    """
    timeout_s = _resolve_sequential_tool_timeout()
    kwargs = {
        "function_name": function_name,
        "function_args": function_args,
        "effective_task_id": effective_task_id,
        "tool_call_id": tool_call_id,
        "execute": execute,
        "scope_block": scope_block,
        "display_index": display_index,
        "middleware_trace": middleware_trace,
    }
    if function_name in _NEVER_PARALLEL_TOOLS:
        return _run_agent_tool_execution_middleware(agent, **kwargs)

    from tools.daemon_pool import DaemonThreadPoolExecutor

    authorization_gate = _ConcurrentToolAuthorizationGate()
    worker_tid: list[int] = []

    def _run() -> _ManagedToolResult:
        with _registered_tool_worker(agent) as tid:
            worker_tid.append(tid)
            return _run_agent_tool_execution_middleware(agent, authorization_gate=authorization_gate, **kwargs)

    ref = _ToolCallRef(
        function_name, function_args, effective_task_id, tool_call_id,
        middleware_trace if middleware_trace is not None else [],
    )
    executor = DaemonThreadPoolExecutor(max_workers=1)
    future = executor.submit(propagate_context_to_thread(_run))
    deadline = time.monotonic() + timeout_s if timeout_s is not None else None
    started = time.monotonic()
    abandoned = False
    try:
        state, result = _poll_sequential_future(agent, future, function_name, deadline, started, authorization_gate)
        if state == "done":
            return result
        if state == "interrupted":
            # Belt-and-braces: interrupt() already fans out to tracked worker
            # tids, but the worker may have registered after the fan-out ran.
            _interrupt_worker_tids(agent, worker_tid, reason=getattr(agent, "_tool_interrupt_reason", None))
            # Grace for a cooperative tool to notice its interrupt bit (mirrors the concurrent path's 3s).
            concurrent.futures.wait([future], timeout=3.0)
            if future.done() and not future.cancelled():
                return future.result()
            abandoned = True  # reuse the abandon-shutdown path in finally
            future.cancel()
            interrupt_reason = getattr(agent, "_tool_interrupt_reason", None) or "interrupt requested"
            message = f"[Tool execution cancelled — {function_name} was abandoned: {interrupt_reason}]"
            logger.info(
                "sequential tool %s abandoned due to %s (%.1fs elapsed)",
                function_name, interrupt_reason, time.monotonic() - started,
            )
            return _abandoned_sequential_result(
                agent, ref, message, _ToolCancelledResult,
                duration_ms=int((time.monotonic() - started) * 1000),
                status="cancelled",
                error_type="tool_interrupted",
                error_message=f"Tool execution cancelled: {interrupt_reason}",
            )

        # Only reachable when a deadline exists (interrupted returns above).
        assert timeout_s is not None
        abandoned = True
        message = f"Error executing tool '{function_name}': timed out after {timeout_s:.1f}s"
        logger.warning("sequential tool %s timed out after %.1fs", function_name, timeout_s)
        future.cancel()
        _interrupt_worker_tids(agent, worker_tid)
        return _abandoned_sequential_result(
            agent, ref, message, _ToolTimeoutResult,
            duration_ms=int(timeout_s * 1000), status="timeout", error_type="tool_timeout", error_message=message,
        )
    finally:
        # Never join a wedged worker. DaemonThreadPoolExecutor also keeps it out
        # of the stdlib atexit join, matching the concurrent timeout path.
        executor.shutdown(wait=not abandoned, cancel_futures=abandoned)


def _begin_tool_execution(
    agent,
    *,
    function_name: str,
    function_args: dict[str, Any],
    effective_task_id: str,
    tool_call_id: str,
    display_index: int | None,
) -> None:
    """Run user-visible and checkpoint preflight on final tool arguments."""
    display_args = _redact_tool_args_for_display(function_name, function_args) or function_args
    if _tool_progress_enabled(agent):
        args_str = json.dumps(display_args, ensure_ascii=False)
        prefix = f"Tool {display_index}" if display_index is not None else "Tool"
        if agent.verbose_logging:
            print(f"  📞 {prefix}: {function_name}({list(display_args.keys())})")
            print(agent._wrap_verbose("Args: ", json.dumps(display_args, indent=2, ensure_ascii=False)))
        else:
            args_preview = args_str[: agent.log_prefix_chars] + "..." if len(args_str) > agent.log_prefix_chars else args_str
            print(f"  📞 {prefix}: {function_name}({list(function_args.keys())}) - {args_preview}")

    agent._current_tool = function_name
    agent._touch_activity(f"executing tool: {function_name}")
    _set_worker_activity_callback(agent)

    if agent.tool_progress_callback:
        try:
            preview = _build_tool_preview(function_name, display_args)
            agent.tool_progress_callback("tool.started", function_name, preview, display_args)
        except Exception as callback_error:
            logging.debug("Tool progress callback error: %s", callback_error)

    if agent.tool_start_callback:
        try:
            agent.tool_start_callback(tool_call_id, function_name, display_args)
        except Exception as callback_error:
            logging.debug("Tool start callback error: %s", callback_error)

    if not agent._checkpoint_mgr.enabled:
        return
    try:
        if function_name in {"write_file", "patch"}:
            _ensure_file_checkpoint(agent, function_name, function_args, effective_task_id)
        elif function_name == "terminal":
            command = function_args.get("command", "")
            if _is_destructive_command(command):
                cwd = function_args.get("workdir") or os.getenv("TERMINAL_CWD", os.getcwd())
                agent._checkpoint_mgr.ensure_checkpoint(cwd, f"before terminal: {command[:60]}")
    except Exception:
        pass


def _emit_tool_completed_progress(agent, function_name: str, *, duration: float, is_error: bool, result) -> None:
    """``tool.completed`` UI projection; downstream of the canonical append so resume
    can reconstruct the result even if the UI bridge dies mid-projection."""
    if not agent.tool_progress_callback:
        return
    try:
        agent.tool_progress_callback(
            "tool.completed", function_name, None, None,
            duration=duration, is_error=is_error, result=result,
        )
    except Exception as cb_err:
        logging.debug("Tool progress callback error: %s", cb_err)


def _emit_tool_complete_and_risk(
    agent, *, function_name: str, function_args: dict, tool_call_id: str, result, risk_metadata, blocked: bool
) -> None:
    """Fire ``tool_complete_callback`` (unless blocked) then the ``tool.output_risk`` projection."""
    if not blocked and agent.tool_complete_callback:
        try:
            display_args = _redact_tool_args_for_display(function_name, function_args) or function_args
            agent.tool_complete_callback(tool_call_id, function_name, display_args, result)
        except Exception as cb_err:
            logging.debug("Tool complete callback error: %s", cb_err)

    if risk_metadata is not None and risk_metadata.get("risk") != "low" and agent.tool_progress_callback:
        try:
            agent.tool_progress_callback(
                "tool.output_risk", function_name, None, None,
                tool_call_id=tool_call_id, risk_metadata=risk_metadata,
            )
        except Exception as cb_err:
            logging.debug("Tool output risk callback error: %s", cb_err)


def _commit_tool_result(
    agent,
    messages: list,
    ref: _ToolCallRef,
    function_result,
    *,
    budget: BudgetConfig,
    tool_duration: float,
    is_error: bool,
    blocked: bool,
    effect_disposition,
):
    """Mark the tool done; persist/spill, hint, wrap and append its result; flush the
    session DB; then project ``tool.completed``.

    Returns ``(persisted_result, display_result, risk_metadata)`` — ``display_result`` is
    the pre-persist content for UI previews — or ``None`` when the flush failed (the
    caller must stop the batch).
    """
    function_name, function_args, tool_call_id, effective_task_id = ref.name, ref.args, ref.call_id, ref.task_id
    agent._current_tool = None
    _status_suffix = " (error)" if is_error else ""
    agent._touch_activity(f"tool completed: {function_name} ({tool_duration:.1f}s){_status_suffix}")

    persisted_result = function_result
    if not _is_multimodal_tool_result(persisted_result):
        persisted_result = maybe_persist_tool_result(
            content=persisted_result,
            tool_name=function_name,
            tool_use_id=tool_call_id,
            env=get_active_env(effective_task_id),
            config=budget,
        )
    _record_persisted_path_for_stub(agent, tool_call_id, persisted_result)

    subdir_hints = agent._subdirectory_hints.check_tool_call(function_name, function_args)
    if subdir_hints:
        if _is_multimodal_tool_result(persisted_result):
            # Hint goes on the text summary part so the model still sees it; image blocks untouched.
            _append_subdir_hint_to_multimodal(persisted_result, subdir_hints)
        else:
            persisted_result += subdir_hints

    # Unwrap _multimodal dicts to an OpenAI-style content list; text-only servers
    # get a string-safe fallback so a rejected image result never poisons history.
    _tool_content = agent._tool_result_content_for_active_model(function_name, persisted_result)
    tool_message = make_tool_result_message(function_name, _tool_content, tool_call_id, effect_disposition=effect_disposition)
    messages.append(tool_message)
    if not _flush_session_db_after_tool_progress(agent, messages, stage=f"tool result {function_name}"):
        return None

    if not blocked:
        _emit_tool_completed_progress(agent, function_name, duration=tool_duration, is_error=is_error, result=function_result)
    return persisted_result, function_result, tool_message.get("_tool_output_risk")


def _observe_and_commit_tool_result(
    agent,
    messages: list,
    ref: _ToolCallRef,
    function_result,
    *,
    budget: BudgetConfig,
    tool_duration: float,
    is_error: bool,
    blocked: bool,
    effect_disposition,
    error_preview: Callable[[Any], Any],
    success_log_chars: Optional[int] = None,
    verbose_text: Callable[[Any], Any] = lambda result: result,
):
    """Guardrail-observe a result that actually ran, log its outcome, feed the turn-end
    file-mutation verifier, then ``_commit_tool_result`` it.

    Blocked calls never ran, so they count as neither failure nor success and are not
    observed. ``success_log_chars`` (sequential path) also logs the completion line.
    """
    function_name, function_args, tool_call_id = ref.name, ref.args, ref.call_id
    if not blocked:
        function_result = agent._append_guardrail_observation(
            function_name, function_args, function_result, failed=is_error, tool_call_id=tool_call_id,
        )
    if is_error:
        logger.warning("Tool %s returned error (%.2fs): %s", function_name, tool_duration, error_preview(function_result))
    elif success_log_chars is not None:
        logger.info("tool %s completed (%.2fs, %d chars)", function_name, tool_duration, success_log_chars)
    if not blocked:
        try:
            agent._record_file_mutation_result(function_name, function_args, function_result, is_error)
        except Exception as _ver_err:
            logging.debug("file-mutation verifier record failed: %s", _ver_err)

    if agent.verbose_logging:
        logging.debug("Tool %s completed in %.2fs", function_name, tool_duration)
        _log_result = verbose_text(function_result)
        logging.debug("Tool result (%d chars): %s", len(_log_result), _log_result)

    return _commit_tool_result(
        agent, messages, ref, function_result,
        budget=budget, tool_duration=tool_duration, is_error=is_error, blocked=blocked,
        effect_disposition=effect_disposition,
    )


def _finalize_tool_batch(agent, messages: list, effective_task_id: str, num_tools: int, budget: BudgetConfig) -> None:
    """Per-turn aggregate budget enforcement, then /steer injection.

    /steer stays pending until AFTER budget enforcement so the steer marker is never
    truncated or discarded when enforcement replaces a tool result; see ``steer()``.
    """
    if num_tools <= 0:
        return
    enforce_turn_budget(messages[-num_tools:], env=get_active_env(effective_task_id), config=budget)
    agent._apply_pending_steer_to_tool_results(messages, num_tools)


def _tool_progress_enabled(agent) -> bool:
    return not agent.quiet_mode and getattr(agent, "tool_progress_mode", "all") != "off"


def _print_tool_completed(agent, index: int, tool_duration: float, result) -> None:
    """Non-quiet ``✅ Tool N completed`` line (full result under verbose logging)."""
    if agent.verbose_logging:
        print(f"  ✅ Tool {index} completed in {tool_duration:.2f}s")
        print(agent._wrap_verbose("Result: ", result))
    else:
        preview = result if isinstance(result, str) else str(result)
        response_preview = preview[:agent.log_prefix_chars] + "..." if len(preview) > agent.log_prefix_chars else preview
        print(f"  ✅ Tool {index} completed in {tool_duration:.2f}s - {response_preview}")


# ── Concurrent batch machinery ──────────────────────────────────────────────


@dataclass
class _ToolOutcome:
    """One finished worker slot of a concurrent batch."""

    name: str
    args: dict
    result: Any
    duration: float
    is_error: bool
    blocked: bool
    middleware_trace: list


def _start_order_gate_timeout(batch_timeout: float | None) -> float:
    """The gate bound must sit UNDER the batch deadline, else parked workers are falsely
    reported timed out without starting. A disabled deadline keeps the stock bound."""
    if batch_timeout is None:
        return _START_ORDER_GATE_TIMEOUT_S
    return min(_START_ORDER_GATE_TIMEOUT_S, batch_timeout / 2)


class _StartOrderGate:
    """Serialize worker dispatch by submit order (prompts appear in call order).

    ``abandon()`` releases every parked worker so none dispatches a tool the turn
    already reported as timed out / interrupted.
    """

    def __init__(self, timeout: float) -> None:
        self._condition = threading.Condition()
        self._next_order = 0
        self._timeout = timeout
        self.abandoned = threading.Event()

    def abandon(self) -> None:
        self.abandoned.set()
        with self._condition:
            self._condition.notify_all()

    def begin_in_order(self, order: int, callback=None, *, tool_name: str = "") -> bool:
        """Wait for ``order``, run ``callback``, advance. Returns False if abandoned."""
        with self._condition:
            # Bounded wait so one wedged dispatch can't starve/leak later-ordered workers;
            # on expiry proceed out of order (interleaved prompts beat starvation).
            # >= (not ==) releases every skipped worker at once; abandoned short-circuits.
            in_order = self._condition.wait_for(
                lambda: self._next_order >= order or self.abandoned.is_set(),
                timeout=self._timeout,
            )
            if self.abandoned.is_set():
                # Do not run the callback or advance the counter: the turn has
                # already synthesized this tool's result and moved on.
                return False
            if not in_order:
                logger.warning(
                    "start-order gate timed out for %s (order=%d next=%d); proceeding out of order",
                    tool_name or "tool", order, self._next_order,
                )
            try:
                if callback is not None:
                    callback()
            finally:
                self._next_order = max(self._next_order, order + 1)
                self._condition.notify_all()
        return True


class _WorkerStartOnce:
    """One worker's handle on the start-order gate: advances at most once, raising
    ``_BatchAbandoned`` (instead of dispatching late) when the batch was abandoned."""

    def __init__(self, gate: _StartOrderGate, order: int, tool_name: str) -> None:
        self._gate, self._order, self._tool_name = gate, order, tool_name
        self._advanced = False

    def advance(self, callback=None) -> None:
        if self._advanced:
            return
        try:
            proceed = self._gate.begin_in_order(self._order, callback, tool_name=self._tool_name)
        finally:
            self._advanced = True
        if not proceed:
            raise _BatchAbandoned(self._tool_name)


class _ConcurrentBatch:
    """Shared state of one concurrent tool batch: per-slot results, the start-order and
    authorization gates, and the deadline bookkeeping the wait loop needs."""

    def __init__(self, agent, messages: list, effective_task_id: str, parsed_calls: list[_ParsedCall], timeout_s: float | None) -> None:
        self.agent = agent
        self.messages = messages
        self.effective_task_id = effective_task_id
        self.parsed_calls = parsed_calls
        self.timeout_s = timeout_s
        self.results: list[Optional[_ToolOutcome]] = [None] * len(parsed_calls)
        for i, pc in enumerate(parsed_calls):
            if pc.parse_error is not None:
                self.results[i] = _ToolOutcome(pc.name, pc.args, pc.parse_error, 0.0, True, True, pc.middleware_trace)
        self.gate = _StartOrderGate(_start_order_gate_timeout(timeout_s))
        self.authorization_gate = _ConcurrentToolAuthorizationGate()
        self.timed_out_indices: set[int] = set()

    def _dispatch_worker(self, index: int, ref: _ToolCallRef, scope_block, start_gate: _WorkerStartOnce) -> Optional[_ToolOutcome]:
        """Run one call through the middleware and synthesize its slot outcome; ``None``
        when the batch was abandoned at the gate (the main thread already wrote this slot,
        so emitting anything would double-report the tool_call_id)."""
        agent = self.agent
        start = time.time()
        blocked = dispatched = False
        try:
            managed = _run_agent_tool_execution_middleware(
                agent,
                function_name=ref.name,
                function_args=ref.args,
                effective_task_id=ref.task_id,
                tool_call_id=ref.call_id,
                execute=lambda next_args: agent._invoke_tool(
                    ref.name,
                    next_args,
                    ref.task_id,
                    ref.call_id,
                    messages=self.messages,
                    pre_tool_block_checked=True,
                    skip_tool_request_middleware=True,
                    skip_tool_execution_middleware=True,
                    tool_request_middleware_trace=list(ref.trace),
                ),
                scope_block=scope_block,
                display_index=index + 1,
                middleware_trace=ref.trace,
                begin_execution=start_gate.advance,
                authorization_gate=self.authorization_gate,
            )
            result, ref.args, ref.trace = managed.result, managed.args, managed.middleware_trace
            blocked, dispatched = managed.blocked, managed.dispatched
        except _BatchAbandoned:
            logger.info("tool %s abandoned at start-order gate; skipping dispatch", ref.name)
            return None
        except KeyboardInterrupt:
            try:
                agent.interrupt("keyboard interrupt")
            except Exception:
                pass
            result = ref.emit_cancelled(agent, start)
            duration = time.time() - start
            logger.info("tool %s cancelled (%.2fs)", ref.name, duration)
            return _ToolOutcome(ref.name, ref.args, result, duration, True, False, ref.trace)
        except Exception as tool_error:
            result = f"Error executing tool '{ref.name}': {tool_error}"
            logger.error("_invoke_tool raised for %s: %s", ref.name, tool_error, exc_info=True)
        duration = time.time() - start
        if not blocked and not dispatched:
            ref.emit_post(agent, result, duration_ms=int(duration * 1000))
        is_error, _ = _detect_tool_failure(ref.name, result)
        if is_error:
            logger.info("tool %s failed (%.2fs): %s", ref.name, duration, result[:200])
        else:
            logger.info("tool %s completed (%.2fs, %d chars)", ref.name, duration, len(result))
        return _ToolOutcome(ref.name, ref.args, result, duration, is_error, blocked, ref.trace)

    def run_worker(self, index, tool_call, function_name, function_args, middleware_trace, scope_block, start_order):
        """Worker function executed in a thread."""
        agent = self.agent
        with _registered_tool_worker(agent) as _worker_tid:
            # Race: interrupt may have fanned out before our registration; apply it to our own tid now.
            if agent._interrupt_requested:
                _interrupt_worker_tids(agent, [_worker_tid], reason=getattr(agent, "_tool_interrupt_reason", None))
            _set_worker_activity_callback(agent)
            # Approval/sudo callbacks and turn ContextVars are propagated by
            # propagate_context_to_thread() at submit.
            start_gate = _WorkerStartOnce(self.gate, start_order, function_name)
            ref = _ToolCallRef(function_name, function_args, self.effective_task_id, _pairing_tool_call_id(tool_call), middleware_trace)
            try:
                outcome = self._dispatch_worker(index, ref, scope_block, start_gate)
                if outcome is not None:
                    self.results[index] = outcome
            finally:
                # Teardown advance keeps later-ordered workers moving; never let the
                # abandonment signal escape here.
                with contextlib.suppress(_BatchAbandoned):
                    start_gate.advance()

    def submit_all(self, executor, runnable_calls) -> tuple[list, dict]:
        """Submit every runnable call; on interpreter shutdown, synthesize error results
        for the unsubmitted remainder instead of raising."""
        futures = []
        future_to_index = {}
        for submit_index, (i, tc, name, args, scope_block) in enumerate(runnable_calls):
            # Propagate turn ContextVars and thread-local approval/sudo
            # callbacks into the worker; clears callbacks on exit.
            try:
                f = executor.submit(
                    propagate_context_to_thread(self.run_worker),
                    i, tc, name, args, self.parsed_calls[i].middleware_trace, scope_block, submit_index,
                )
            except RuntimeError as submit_error:
                if not _is_interpreter_shutdown_submit_error(submit_error):
                    raise
                skipped_calls = runnable_calls[submit_index:]
                logger.warning(
                    "interpreter shutdown while scheduling concurrent tools; skipping %d unsubmitted tool(s)",
                    len(skipped_calls),
                )
                for skipped_i, _tc, skipped_name, skipped_args, _scope_block in skipped_calls:
                    if self.results[skipped_i] is None:
                        result = (
                            f"Error executing tool '{skipped_name}': "
                            "Python interpreter is shutting down; tool was not started"
                        )
                        self.results[skipped_i] = _ToolOutcome(
                            skipped_name, skipped_args, result, 0.0, True, False,
                            self.parsed_calls[skipped_i].middleware_trace,
                        )
                break
            futures.append(f)
            future_to_index[f] = i
        return futures, future_to_index

    def _running_names(self, not_done, future_to_index) -> list[str]:
        return [self.parsed_calls[future_to_index[f]].name for f in not_done if f in future_to_index]

    def await_completion(self, futures, future_to_index, deadline: float | None) -> bool:
        """Wait with periodic heartbeats (gateway inactivity monitor) and interrupt checks
        (/stop or a new message). Returns True when the batch was abandoned (deadline or
        interrupt) and the executor must not join its workers."""
        agent = self.agent
        _conc_start = time.time()
        while True:
            wait_timeout = 5.0
            if deadline is not None:
                effective_deadline = deadline + self.authorization_gate.excluded_seconds()
                remaining = effective_deadline - time.monotonic()
                if remaining <= 0:
                    done, not_done = set(), {f for f in futures if not f.done()}
                else:
                    wait_timeout = min(wait_timeout, remaining)
                    done, not_done = concurrent.futures.wait(futures, timeout=wait_timeout)
            else:
                done, not_done = concurrent.futures.wait(futures, timeout=wait_timeout)
            if not not_done:
                return False

            if deadline is not None and time.monotonic() >= deadline + self.authorization_gate.excluded_seconds():
                self.timed_out_indices = {future_to_index[f] for f in not_done if f in future_to_index}
                logger.warning(
                    "concurrent tool batch timed out after %.1fs; %d tool(s) still running: %s",
                    self.timeout_s,
                    len(self.timed_out_indices),
                    ", ".join(self._running_names(not_done, future_to_index)[:5]),
                )
                for f in not_done:
                    f.cancel()
                # Release gate-parked workers before interrupt fan-out so none
                # later dispatches a tool just reported as timed out.
                self.gate.abandon()
                with agent._tool_worker_threads_lock:
                    worker_tids = list(agent._tool_worker_threads)
                _interrupt_worker_tids(agent, worker_tids)
                return True

            # Tools without interrupt checks (web_search, read_file) run to
            # completion; cancel unstarted futures so we don't block on them.
            if agent._interrupt_requested:
                agent._vprint(
                    f"{agent.log_prefix}⚡ Interrupt: cancelling {len(not_done)} pending concurrent tool(s)",
                    force=True,
                )
                for f in not_done:
                    f.cancel()
                # Release gate-parked workers so they abort instead of dispatching after
                # the turn was already interrupted; then give running tools a moment to
                # notice the per-thread interrupt signal and exit gracefully.
                self.gate.abandon()
                concurrent.futures.wait(not_done, timeout=3.0)
                return True

            _conc_elapsed = int(time.time() - _conc_start)
            # Heartbeat every ~30s (6 × 5s poll intervals)
            if _conc_elapsed > 0 and _conc_elapsed % 30 < 6:
                _still_running = self._running_names(not_done, future_to_index)
                agent._touch_activity(
                    f"concurrent tools running ({_conc_elapsed}s, "
                    f"{len(not_done)} remaining: {', '.join(_still_running[:3])})"
                )

    def run(self) -> None:
        """Dispatch the runnable calls on a daemon pool and wait for the batch."""
        runnable_calls = [
            (i, pc.tool_call, pc.name, pc.args, pc.scope_block)
            for i, pc in enumerate(self.parsed_calls)
            if pc.parse_error is None
        ]
        if not runnable_calls:
            return
        deadline = time.monotonic() + self.timeout_s if self.timeout_s is not None else None
        max_workers = _max_workers_for_tool_batch(runnable_calls)
        # Daemon workers: stdlib ThreadPoolExecutor's atexit join would let one
        # wedged tool thread block interpreter exit forever.
        from tools.daemon_pool import DaemonThreadPoolExecutor
        executor = DaemonThreadPoolExecutor(max_workers=max_workers)
        abandon_executor = False
        try:
            futures, future_to_index = self.submit_all(executor, runnable_calls)
            abandon_executor = self.await_completion(futures, future_to_index, deadline)
        finally:
            # Any abandoning exit from the wait loop (including the exception
            # path) must release gate-parked workers.
            if abandon_executor:
                self.gate.abandon()
            # On abandon do NOT join hung workers: a wedged thread is left detached
            # rather than deadlocking the batch. Normal completion joins.
            executor.shutdown(wait=not abandon_executor, cancel_futures=abandon_executor)


def _unfinished_tool_result(agent, ref: _ToolCallRef, *, timed_out: bool, timeout_s: float | None) -> tuple[str, float, Optional[str]]:
    """Synthesize the result for a slot no worker filled (deadline, interrupt, or a
    thread that never returned) and emit its terminal post_tool_call.

    Returns ``(function_result, tool_duration, effect_disposition)``.
    """
    if timed_out:
        suffix = f"{timeout_s:.1f}s" if timeout_s is not None else "the configured timeout"
        function_result = f"Error executing tool '{ref.name}': timed out after {suffix}"
        outcome = dict(duration_ms=int((timeout_s or 0.0) * 1000), status="timeout", error_type="tool_timeout", error_message=function_result)
        tool_duration, effect_disposition = float(timeout_s or 0.0), "unknown"
    elif agent._interrupt_requested:
        function_result = f"[Tool execution cancelled — {ref.name} was skipped due to user interrupt]"
        outcome = dict(status="cancelled", error_type="keyboard_interrupt", error_message="Tool execution cancelled by user interrupt")
        tool_duration, effect_disposition = 0.0, None
    else:
        function_result = f"Error executing tool '{ref.name}': thread did not return a result"
        outcome = dict(status="error", error_type="thread_missing_result", error_message=function_result)
        tool_duration, effect_disposition = 0.0, None
    ref.emit_post(agent, function_result, **outcome)
    return function_result, tool_duration, effect_disposition


def _append_batch_results(agent, messages: list, effective_task_id: str, batch: _ConcurrentBatch, budget: BudgetConfig) -> bool:
    """Append every slot's result in original call order; returns False at the first
    failed flush (the caller must stop the batch)."""
    for i, pc in enumerate(batch.parsed_calls):
        r = batch.results[i]
        ref = pc.ref(effective_task_id)
        # A worker may finish between the deadline snapshot and this loop;
        # prefer its real result over a fabricated timeout.
        if r is None:
            blocked = False
            function_result, tool_duration, effect_disposition = _unfinished_tool_result(
                agent, ref, timed_out=i in batch.timed_out_indices, timeout_s=batch.timeout_s,
            )
            committed = _commit_tool_result(
                agent, messages, ref, function_result,
                budget=budget, tool_duration=tool_duration, is_error=True, blocked=False,
                effect_disposition=effect_disposition,
            )
        else:
            ref.name, ref.args, ref.trace, tool_duration, blocked = r.name, r.args, r.middleware_trace, r.duration, r.blocked
            if pc.parse_error is not None:
                ref.emit_invalid_arguments(agent, r.result)
            committed = _observe_and_commit_tool_result(
                agent, messages, ref, r.result,
                budget=budget, tool_duration=tool_duration, is_error=r.is_error, blocked=blocked,
                effect_disposition="none" if blocked else None,
                error_preview=lambda res: _multimodal_text_summary(res)[:200],
            )
        if committed is None:
            return False
        _persisted, display_function_result, risk_metadata = committed

        if agent._should_emit_quiet_tool_messages():
            cute_msg = _get_cute_tool_message_impl(ref.name, ref.args, tool_duration, result=display_function_result)
            agent._safe_print(f"  {cute_msg}")
        elif _tool_progress_enabled(agent):
            _print_tool_completed(agent, i + 1, tool_duration, _multimodal_text_summary(display_function_result))

        _emit_tool_complete_and_risk(
            agent,
            function_name=ref.name,
            function_args=ref.args,
            tool_call_id=ref.call_id,
            result=display_function_result,
            risk_metadata=risk_metadata,
            blocked=blocked,
        )
    return True


def execute_tool_calls_concurrent(agent, assistant_message, messages: list, effective_task_id: str, api_call_count: int = 0, *, finalize: bool = True) -> None:
    """Execute tool calls concurrently; results are appended in original call order.

    ``finalize=False`` skips end-of-batch budget enforcement and /steer injection (the
    segmented dispatcher owns turn-end work).
    """
    tool_calls = assistant_message.tool_calls
    num_tools = len(tool_calls)

    # Resolve the context-scaled tool-output budget once per turn, not per result.
    _tool_budget = _budget_for_agent(agent)

    if agent._interrupt_requested:
        print(f"{agent.log_prefix}⚡ Interrupt: skipping {num_tools} tool call(s)")
        _append_skipped_tool_results(
            agent, messages, tool_calls, effective_task_id,
            content="[Tool execution cancelled — {name} was skipped due to user interrupt]",
            hook_error_type="user_interrupt",
            flush_stage="cancelled tool result",
            stop_on_flush_failure=False,
        )
        return

    parsed_calls = [_parse_tool_call(agent, tc) for tc in tool_calls]

    tool_names_str = ", ".join(pc.name for pc in parsed_calls)
    if _tool_progress_enabled(agent):
        print(f"  ⚡ Concurrent: {num_tools} tool calls — {tool_names_str}")

    # Resolved before the batch is built so the start-order gate can clamp
    # its own bound against the batch deadline it must stay under.
    timeout_s = _resolve_concurrent_tool_timeout()
    batch = _ConcurrentBatch(agent, messages, effective_task_id, parsed_calls, timeout_s)

    # Touch activity before launching workers so the gateway knows we're executing tools.
    agent._current_tool = tool_names_str
    agent._touch_activity(f"executing {num_tools} tools concurrently: {tool_names_str}")

    spinner = _start_quiet_tool_spinner(agent, "", {}, label=f"⚡ running {num_tools} tools concurrently")
    try:
        batch.run()
    finally:
        if spinner:
            finished = [r for r in batch.results if r is not None]
            total_dur = sum(r.duration for r in finished)
            spinner.stop(f"⚡ {len(finished)}/{num_tools} tools completed in {total_dur:.1f}s total")

    if not _append_batch_results(agent, messages, effective_task_id, batch, _tool_budget):
        return
    if finalize:
        _finalize_tool_batch(agent, messages, effective_task_id, len(parsed_calls), _tool_budget)


# ── Sequential dispatch ─────────────────────────────────────────────────────


def _start_quiet_tool_spinner(agent, function_name: str, function_args: dict, *, gate: bool = True, label: Optional[str] = None):
    """Start the quiet-mode kawaii spinner for one tool call, or return None.

    ``gate=False`` skips ``_should_start_quiet_spinner`` (context-engine tools always spin).
    """
    if not agent._should_emit_quiet_tool_messages():
        return None
    if gate and not agent._should_start_quiet_spinner():
        return None
    face = random.choice(KawaiiSpinner.get_waiting_faces())
    if label is None:
        emoji = _get_tool_emoji(function_name)
        display_args = _redact_tool_args_for_display(function_name, function_args) or function_args
        label = f"{emoji} {_build_tool_label(function_name, display_args) or function_name}"
    spinner = KawaiiSpinner(f"{face} {label}", spinner_type='dots', print_fn=agent._print_fn)
    spinner.start()
    return spinner


def _finish_quiet_tool_spinner(agent, spinner, function_name: str, function_args: dict, tool_duration: float, result) -> None:
    """Stop the spinner with the cute completion line, or print it when no spinner ran."""
    if spinner:
        spinner.stop(_get_cute_tool_message_impl(function_name, function_args, tool_duration, result=result))
    elif agent._should_emit_quiet_tool_messages():
        agent._vprint(f"  {_get_cute_tool_message_impl(function_name, function_args, tool_duration, result=result)}")


def _delegate_spinner_label(function_args: dict) -> str:
    _action_arg = str(function_args.get("action") or "").strip().lower()
    tasks_arg = function_args.get("tasks")
    if _action_arg in ("list", "steer", "stop"):
        return f"🔀 subagent {_action_arg}"
    if tasks_arg and isinstance(tasks_arg, list):
        return f"🔀 delegating {len(tasks_arg)} tasks · (/agents to monitor)"
    goal_preview = (function_args.get("goal") or "")[:30]
    return f"🔀 {goal_preview} · (/agents to monitor)" if goal_preview else "🔀 delegating · (/agents to monitor)"


@dataclass
class _SequentialDispatch:
    """How one sequential call executes: the callable plus its spinner/error policy."""

    execute: Callable[[dict], Any]
    spinner: Any = None
    # Passed through to the middleware runner; the registry closure reads this list.
    middleware_trace_arg: Optional[list] = None
    # None → exceptions propagate (inline / delegate tools own their failures).
    error_result: Optional[Callable[[Exception], str]] = None
    error_log: str = ""
    handles_keyboard_interrupt: bool = False
    is_delegate: bool = False
    finish_spinner: bool = True
    # Inline tools print their completion line only on success (no try/finally).
    finish_in_finally: bool = True


def _resolve_sequential_dispatch(
    agent,
    *,
    function_name: str,
    function_args: dict,
    messages: list,
    effective_task_id: str,
    tool_call_id: str,
    middleware_trace: list,
) -> _SequentialDispatch:
    """Pick the execute callable for one sequential call and start its spinner.

    Precedence is the historical if/elif order: inline agent-level tools, delegate_task,
    context-engine tools, memory-provider tools, then the registry.
    """
    if function_name != "delegate_task" and function_name in INLINE_TOOL_EXECUTORS:
        # Agent-level tools that need live AIAgent state; table shared with invoke_tool.
        inline_executor = INLINE_TOOL_EXECUTORS[function_name]
        inline_ctx = InlineToolContext(effective_task_id=effective_task_id, tool_call_id=tool_call_id, messages=messages)
        return _SequentialDispatch(
            execute=lambda next_args: inline_executor(agent, next_args, inline_ctx),
            finish_in_finally=False,
        )
    if function_name == "delegate_task":
        spinner = _start_quiet_tool_spinner(agent, function_name, function_args, label=_delegate_spinner_label(function_args))
        agent._delegate_spinner = spinner
        return _SequentialDispatch(
            execute=lambda next_args: agent._dispatch_delegate_task(next_args),
            spinner=spinner,
            is_delegate=True,
        )
    if agent._context_engine_tool_names and function_name in agent._context_engine_tool_names:
        # Context engine tools (lcm_grep, lcm_describe, lcm_expand, etc.)
        return _SequentialDispatch(
            execute=lambda next_args: agent.context_compressor.handle_tool_call(function_name, next_args, messages=messages),
            spinner=_start_quiet_tool_spinner(agent, function_name, function_args, gate=False),
            error_result=lambda e: json.dumps({"error": f"Context engine tool '{function_name}' failed: {e}"}),
            error_log="context_engine.handle_tool_call raised for %s: %s",
        )
    if agent._memory_manager and agent._memory_manager.has_tool(function_name):
        # Memory provider tools (hindsight_retain, honcho_search, etc.) are not in the
        # tool registry — route through MemoryManager.
        return _SequentialDispatch(
            execute=lambda next_args: agent._memory_manager.handle_tool_call(function_name, next_args),
            spinner=_start_quiet_tool_spinner(agent, function_name, function_args),
            error_result=lambda e: json.dumps({"error": f"Memory tool '{function_name}' failed: {e}"}),
            error_log="memory_manager.handle_tool_call raised for %s: %s",
        )

    # Registry tools: post hook is owned by this executor (inner observer suppressed).
    def _execute(next_args: dict) -> Any:
        from model_tools import suppress_post_tool_call_hook

        with suppress_post_tool_call_hook():
            return _ra().handle_function_call(
                function_name,
                next_args,
                effective_task_id,
                tool_call_id=tool_call_id,
                session_id=agent.session_id or "",
                turn_id=getattr(agent, "_current_turn_id", "") or "",
                api_request_id=getattr(agent, "_current_api_request_id", "") or "",
                enabled_tools=list(agent.valid_tool_names) if agent.valid_tool_names else None,
                skip_pre_tool_call_hook=True,
                skip_tool_request_middleware=True,
                skip_tool_execution_middleware=True,
                tool_request_middleware_trace=list(middleware_trace),
                enabled_toolsets=getattr(agent, "enabled_toolsets", None),
                disabled_toolsets=getattr(agent, "disabled_toolsets", None),
            )

    return _SequentialDispatch(
        execute=_execute,
        spinner=_start_quiet_tool_spinner(agent, function_name, function_args) if agent.quiet_mode else None,
        middleware_trace_arg=middleware_trace,
        error_result=lambda e: f"Error executing tool '{function_name}': {e}",
        error_log="handle_function_call raised for %s: %s",
        handles_keyboard_interrupt=True,
        finish_spinner=bool(agent.quiet_mode),
    )


def _skip_remaining_sequential(agent, messages: list, remaining, effective_task_id: str, *, notice: str, **skip_kwargs) -> bool:
    """Announce an interrupt and append one skipped result per unstarted call; False when
    a flush failed (the caller must stop the batch)."""
    agent._vprint(f"{agent.log_prefix}⚡ Interrupt: skipping {len(remaining)} {notice}", force=True)
    return _append_skipped_tool_results(agent, messages, remaining, effective_task_id, **skip_kwargs)


def _append_invalid_arguments_result(agent, messages: list, ref: _ToolCallRef, parse_error: str) -> bool:
    """Emit + append the parse-error result for a call whose arguments were not a JSON object."""
    ref.emit_invalid_arguments(agent, parse_error)
    messages.append(make_tool_result_message(ref.name, parse_error, ref.call_id))
    return _flush_session_db_after_tool_progress(agent, messages, stage=f"invalid tool arguments {ref.name}")


def _run_sequential_call(
    agent,
    dispatch: _SequentialDispatch,
    ref: _ToolCallRef,
    *,
    scope_block: Optional[str],
    messages: list,
    remaining_calls,
    display_index: int,
    tool_start_time: float,
) -> tuple[_ManagedToolResult, float]:
    """Run one sequential call with its spinner/error policy; returns ``(managed, duration)``.

    KeyboardInterrupt (registry tools only) emits results for THIS and every remaining
    call before re-raising so the tool-call turn keeps matching results (alternation).
    """
    _spinner_result = None
    try:
        managed = _run_sequential_tool_execution_middleware(
            agent,
            function_name=ref.name,
            function_args=ref.args,
            effective_task_id=ref.task_id,
            tool_call_id=ref.call_id,
            execute=dispatch.execute,
            scope_block=scope_block,
            display_index=display_index,
            middleware_trace=dispatch.middleware_trace_arg,
        )
        ref.args = managed.args
        _spinner_result = managed.result
    except KeyboardInterrupt:
        if not dispatch.handles_keyboard_interrupt:
            raise
        _spinner_result = ref.emit_cancelled(agent, tool_start_time)
        try:
            agent.interrupt("keyboard interrupt")
        except Exception:
            pass
        _append_skipped_tool_results(
            agent, messages, remaining_calls, ref.task_id,
            content="[Tool execution cancelled — {name} was skipped due to keyboard interrupt]",
        )
        raise
    except Exception as tool_error:
        if dispatch.error_result is None:
            raise
        function_result = dispatch.error_result(tool_error)
        logger.error(dispatch.error_log, ref.name, tool_error, exc_info=True)
        managed = _ManagedToolResult(result=function_result, args=ref.args, middleware_trace=ref.trace, blocked=False, dispatched=False)
    finally:
        if dispatch.is_delegate:
            agent._delegate_spinner = None
        tool_duration = time.time() - tool_start_time
        if dispatch.finish_spinner and dispatch.finish_in_finally:
            _finish_quiet_tool_spinner(agent, dispatch.spinner, ref.name, ref.args, tool_duration, _spinner_result)
    if dispatch.finish_spinner and not dispatch.finish_in_finally:
        _finish_quiet_tool_spinner(agent, dispatch.spinner, ref.name, ref.args, tool_duration, _spinner_result)
    return managed, tool_duration


def _publish_sequential_result(agent, messages: list, ref: _ToolCallRef, managed: _ManagedToolResult, *, tool_duration: float, index: int, budget: BudgetConfig) -> bool:
    """Terminal hook → observe → commit → completion callbacks/print for one sequential
    result; False when the incremental flush failed (the caller must stop the batch)."""
    ref.args, ref.trace, function_result = managed.args, managed.middleware_trace, managed.result
    _execution_timed_out = isinstance(function_result, (_ToolTimeoutResult, _ToolCancelledResult))
    # Multimodal dict results (_multimodal=True) are not sliceable as strings.
    _result_len = len(function_result) if isinstance(function_result, str) else len(str(function_result))
    _is_error_result, _ = _detect_tool_failure(ref.name, function_result)
    # Inline-dispatched runtime tools never reach handle_function_call, so the
    # executor owns the one terminal post_tool_call per tool_call_id (the inner
    # observer is suppressed); also stops an abandoned timeout worker reporting late.
    if not managed.blocked and not _execution_timed_out:
        ref.emit_post(agent, function_result, duration_ms=int(tool_duration * 1000))
    committed = _observe_and_commit_tool_result(
        agent, messages, ref, function_result,
        budget=budget, tool_duration=tool_duration, is_error=_is_error_result, blocked=managed.blocked,
        effect_disposition="unknown" if _execution_timed_out else None,
        error_preview=lambda res: res[:200] if isinstance(res, str) and not agent.verbose_logging else res,
        success_log_chars=_result_len,
        verbose_text=_multimodal_text_summary,
    )
    if committed is None:
        return False
    function_result, display_function_result, risk_metadata = committed

    _emit_tool_complete_and_risk(
        agent,
        function_name=ref.name,
        function_args=ref.args,
        tool_call_id=ref.call_id,
        result=display_function_result,
        risk_metadata=risk_metadata,
        blocked=managed.blocked,
    )
    if _tool_progress_enabled(agent):
        _print_tool_completed(agent, index, tool_duration, function_result)
    return True


def execute_tool_calls_sequential(agent, assistant_message, messages: list, effective_task_id: str, api_call_count: int = 0, *, finalize: bool = True) -> None:
    """Execute tool calls sequentially (single calls or interactive tools).

    ``finalize=False`` skips end-of-batch budget enforcement and /steer injection (the
    segmented dispatcher owns turn-end work).
    """
    # Resolve the context-scaled tool-output budget once per turn, not per result.
    _tool_budget = _budget_for_agent(agent)
    tool_calls = assistant_message.tool_calls

    for i, tool_call in enumerate(tool_calls, 1):
        tool_call_id = _pairing_tool_call_id(tool_call)
        if getattr(agent, "_incremental_persistence_failed", False):
            return
        # SAFETY: check interrupt BEFORE each tool so a "stop" during the previous
        # tool skips all remaining ones.
        if agent._interrupt_requested:
            if not _skip_remaining_sequential(
                agent, messages, tool_calls[i - 1:], effective_task_id,
                notice="tool call(s)",
                content="[Tool execution cancelled — {name} was skipped due to user interrupt]",
                hook_error_type="user_interrupt",
                hook_id=lambda tc: getattr(tc, "id", "") or "",
                flush_stage="cancelled tool result",
            ):
                return
            break

        pc = _parse_tool_call(agent, tool_call, flatten_probe=True)
        ref = pc.ref(effective_task_id)
        if pc.parse_error is not None:
            if not _append_invalid_arguments_result(agent, messages, ref, pc.parse_error):
                return
            continue

        tool_start_time = time.time()
        # One bounded execution funnel for every runtime-tool branch; no duplicated
        # timeout policy in the callbacks.
        dispatch = _resolve_sequential_dispatch(
            agent,
            function_name=ref.name,
            function_args=ref.args,
            messages=messages,
            effective_task_id=effective_task_id,
            tool_call_id=tool_call_id,
            middleware_trace=ref.trace,
        )
        managed, tool_duration = _run_sequential_call(
            agent, dispatch, ref,
            scope_block=pc.scope_block,
            messages=messages,
            remaining_calls=tool_calls[i - 1:],
            display_index=i,
            tool_start_time=tool_start_time,
        )
        if not _publish_sequential_result(agent, messages, ref, managed, tool_duration=tool_duration, index=i, budget=_tool_budget):
            return

        if agent._interrupt_requested and i < len(tool_calls):
            if not _skip_remaining_sequential(
                agent, messages, tool_calls[i:], effective_task_id,
                notice="remaining tool call(s)",
                content="[Tool execution skipped — {name} was not started. User sent a new message]",
                flush_stage="skipped tool result",
            ):
                return
            break

    if finalize:
        _finalize_tool_batch(agent, messages, effective_task_id, len(tool_calls), _tool_budget)


def execute_tool_calls_segmented(agent, assistant_message, messages: list, effective_task_id: str, api_call_count: int = 0, segments=None) -> None:
    """Execute a mixed batch as ordered parallel/sequential segments.

    ``segments`` is the ``(kind, calls)`` plan from ``_plan_tool_batch_segments``;
    contiguous segments preserve per-call result order and barrier boundaries exactly
    as fully-sequential execution. Turn-end work (budget + /steer) runs once here;
    segment executors run with ``finalize=False``. Each segment executor checks the
    interrupt flag up front, so an interrupt drains later segments with one result per call.
    """
    from types import SimpleNamespace

    if segments is None:
        _active_env = get_active_env(effective_task_id)
        _exec_cwd = Path(_active_env.cwd) if _active_env is not None and _active_env.cwd else None
        segments = _plan_tool_batch_segments(assistant_message.tool_calls, execution_cwd=_exec_cwd)

    for kind, calls in segments:
        if getattr(agent, "_incremental_persistence_failed", False):
            return
        segment_message = SimpleNamespace(tool_calls=list(calls))
        run_segment = execute_tool_calls_concurrent if kind == "parallel" else execute_tool_calls_sequential
        run_segment(agent, segment_message, messages, effective_task_id, api_call_count, finalize=False)
        if getattr(agent, "_incremental_persistence_failed", False):
            return

    total_tools = len(assistant_message.tool_calls)
    if total_tools > 0:
        _finalize_tool_batch(agent, messages, effective_task_id, total_tools, _budget_for_agent(agent))


__all__ = [
    "execute_tool_calls_concurrent",
    "execute_tool_calls_sequential",
    "execute_tool_calls_segmented",
]