Composio-style MCP servers return un-paginated 22-47K-char payloads that
sail under the generic 100K per-result spillover threshold, bloating
context and ballooning per-turn reasoning time on long conversations.
Competitors cap harder (OpenCode/pi 50KB, Claude Code 30K, Codex ~10K
tokens). Three changes:
- mcp_* tools spill at a tighter 50K default (BudgetConfig.mcp_result_size,
config-overridable via tool_budget.mcp_result_size_chars; pinned and
per-tool overrides still win; capped by the context-scaled default).
- The persisted-output preview now teaches recovery: page the saved file
with read_file or process with execute_code instead of re-requesting the
same data from the remote API.
- Untrusted/MCP string results are scanned (bounded, first 64KB) for
provider-side elision markers ('...N more items', "has_more": true,
'saved to sandbox', data_preview) and get ONE cache-safe incompleteness
notice appended at result-construction time, before untrusted wrapping —
so the model stops treating provider-elided enumerations as complete.
- Hard 2M-char allocation cap in mcp_tool.py (text, error, and
structuredContent paths) so a pathological multi-MB server payload is
bounded before it propagates, while ordinary large results reach
spillover intact. Distilled from #56060/#56072/#56511 (issue #56059);
supersedes their 50K lossy truncation with spillover-friendly semantics.
Docs: configuration.md spillover-budget section + cli-config.yaml.example.
Co-authored-by: Stoltemberg <215755014+Stoltemberg@users.noreply.github.com>
Co-authored-by: AlexFucuson9 <295703459+AlexFucuson9@users.noreply.github.com>
Co-authored-by: Tranquil-Flow <66773372+Tranquil-Flow@users.noreply.github.com>
The tool-result persistence budget was a fixed 100K chars/result and 200K
chars/turn regardless of the active model. On a small-context model (e.g. a
65K-token local model switched into mid-session) a single large tool result
(reporter: a 279K-char search result) or a full 200K-char turn (~50K tokens)
could by itself approach or exceed the window, forcing an oversized request
that the provider rejects as "Prompt too long".
- budget_config.budget_for_context_window() scales per-result/per-turn char
caps to a fraction of the model window, clamped to the historical 100K/200K
defaults (large models unchanged) and floored so small models stay usable.
- resolve_threshold() now caps the per-tool registry value at default_result_size
so tools that register a fixed 100K cap (web/terminal/x_search) don't re-inflate
a scaled-down budget. No-op for the default budget (both 100K).
- tool_executor wires the agent's live context_length (recomputed on model
switch) into all four persist/turn-budget call sites.
read_file stays inf-pinned (no persist loop). Verified E2E: a 279K-char result
against a 65K model collapses to a ~1.6K preview; a 200K model is byte-identical
to today.
- DEFAULT_RESULT_SIZE_CHARS: 50K -> 100K (match current _LARGE_RESULT_CHARS)
- DEFAULT_PREVIEW_SIZE_CHARS: 2K -> 1.5K (match current _LARGE_RESULT_PREVIEW_CHARS)
- Per-tool overrides all set to 100K (terminal, execute_code, search_files)
- Remove pre-read byte guard (no behavioral regression vs current main)
- Revert limit signature change to int=500 (match current default)
- Restore original read_file schema description
- Update test assertions to match 100K thresholds
Add BudgetConfig dataclass to centralize and make overridable the
hardcoded constants (50K per-result, 200K per-turn, 2K preview) that
control when tool outputs get persisted to sandbox. Configurable at
the RL environment level via HermesAgentEnvConfig fields, threaded
through HermesAgentLoop to the storage layer.
Resolution: pinned (read_file=inf) > env config overrides > registry
per-tool > default. CLI override: --env.turn_budget_chars 80000