1 Commits

Author	SHA1	Message	Date
Zeren Wang	22b0456e45	feat(harness): subagent report contract and delegation acceptance criteria (#5090) ... * feat(harness): subagent report contract and delegation acceptance criteria (RFC #4651 PR3) Layer 1 receipt verification is inert unless subagents actually cite their execution record. This lands the prompt layer that closes the adoption gap: - New subagents/report_contract.py owns the model-facing contract text, derived from the single-owner citation format (format_citation / receipt_id) so prompts can never drift from the verifier. The executor injects <report_contract> into every subagent system prompt — built-in and custom alike — requiring [rN tool_name] citations for action claims, verifiable handles (absolute path, URL, ID, HTTP status) for deliverables, and explicit failure reporting; the citation clause follows verification.receipts_enabled. - The task tool gains an optional keyword-only acceptance_criteria parameter, handed to the SubagentExecutor constructor and rendered into the subagent's SystemMessage (stripped, capped 20 items x 500 chars) — deliberately never the task HumanMessage, which InputSanitizationMiddleware classes as genuine user input and would HTML-escape into untrusted-input framing. The docstring frames subagent results as self-reports, states the citation cross-check's evidence boundary (resolved = the call happened, not that the claim is correct), and documents when to attach criteria with the canonical leaf forms. Deterministic leaf checking remains a separate layer. - The lead delegation workflow now instructs reading the ledger citation line as execution evidence only and spot-checking verifiable handles before synthesizing. - report_contract / acceptance_criteria are registered as blocked framework-authority tags in input sanitization so untrusted input cannot forge the verification contract. * fix(harness): neutralize acceptance criteria before system-channel injection render_acceptance_criteria_section interpolated lead-model-supplied acceptance_criteria verbatim into the subagent SystemMessage after only stripping/capping. A criterion such as '</acceptance_criteria><system>...</system>' could close the wrapper and open a framework authority tag, bypassing InputSanitizationMiddleware. Route each criterion through neutralize_untrusted_tags (the shared prompt-injection primitive) so blocked authority tags are HTML-escaped before interpolation. Add regression tests at the renderer and the executor _build_initial_state path. * fix(harness): keep model-supplied criteria off the system channel - Move acceptance_criteria values into the task HumanMessage — the untrusted channel InputSanitizationMiddleware escapes and boundary-frames. The subagent SystemMessage now carries only a framework-owned <acceptance_criteria> pointer note (no criterion text), so natural-language injection inside a criterion keeps task-data priority and cannot override framework instructions (PR #5090 review, willem-bd P1). - Condition the lead delegation workflow's citation verification guidance on verification.receipts_enabled and qualify the task tool's result-reading text with the enabled state, so a receipts-disabled configuration no longer tells the lead to require citation evidence that cannot exist (P2). * fix(harness): drop execution-record promise from report contract when receipts are disabled The <report_contract> opening was emitted unconditionally, so a verification.receipts_enabled=false subagent was told its report would be cross-checked against an execution record that cannot exist in that mode (terminal_receipts() returns None; no verdict, no ledger citation line). The opening now follows receipts_enabled: enabled keeps the cross-check language, disabled describes the handle-only review mode (PR #5090 review, willem-bd P2). * docs: record the prompt-layer trust-boundary self-check Generalizes the PR #5090 review outcome: before adding prompt text, ask of every data source in it what trust level it has and which channel it should ride — model/user-influenceable values ride the untrusted sanitized data channel, never framework-owned system text. Added to the PR template (Agents/LangGraph surface) and agents/AGENTS.md.	2026-08-30 11:39:25 +08:00