[kentwelcome]

Summary

Fix false blockers that prevented behavior-rehearse from completing a supported comparison.

• Derive required capabilities from the owner's claims. Missing production tools do not block a disclosed, controlled decision rehearsal; explicit real-output goals keep their real dependencies.
• Accept complete paginated Codex native preparation records with strict cursor-chain, identity, input, single-turn, and completion validation. Preserve unavailable and unverified evidence facets.
• Clarify supplied-history freshness and process-local preparation controls for memory, hooks, plugins, apps, agents, web access, and MCP servers. Inspect effective configuration rather than assuming an empty server map disables inherited servers.
• Distinguish host command permission from trial isolation without weakening child sandboxes or approval requirements.
• Tighten extraction instructions for final-chain indexes and exact trial-local citations; validators remain unchanged.
• Update canonical workflow references, architecture, manual verification guidance, and synthetic regression coverage.

Closes DRC-5022.

Observed manual verification

A fresh Codex coordinator completed preparation, three Before trials, three After trials, assessment, raw-evidence audit, and its final recommendation in one uninterrupted turn without parent repair or stage-by-stage intervention. All six native trial records show completed turns and exit code zero. Preparation's effective configuration showed the documented controls disabled; normal child sandboxes were retained.

Assessment limitation: three of ten automated checks were rejected and subsequently audited against raw evidence. The original reports were not rewritten. This verifies the execution/refusal fixes, not universal assessment reliability or an all-checks-passed result. The run used modified local source; live Claude Code execution was not tested.

Real source cases, transcripts, credentials, reports, and run artifacts remain outside the repository.

Deterministic verification

Passed:

• Full deterministic command list from AGENTS.md.
• python3 tests/preparation-evidence-test.py — 9 tests.
• python3 tests/shared-data-test.py — 31 tests, 1 platform skip.
• Additional CI contracts: progress status, progress assessment, native context boundaries, Codex isolation, Jev, and version-bump self-check. Platform-specific skips remain reported by the suites.
• Bash formatting with mvdan/shfmt:v3.14.0.
• uvx [email protected] format --check --diff . — 170 files formatted.
• git diff --check.

Independent review

Two independent read-only reviews of the complete tracked change followed REVIEWER_GUIDELINES.md:

• Standards, safety, native evidence and downstream consumers: APPROVE, no findings.
• User requirements, workflow semantics and approval boundaries: APPROVE, no findings.

Scope

No new dependency, model-backed CI gate, replacement launcher, global configuration mutation, version bump, merge, or release. One focused DCO-signed commit: 70e389b45b138931aefbd65fc8cd163061df2d73.

[github-actions]

Behavior Diff · plugin/skills/behavior-diff-live/SKILL.md

Run status: Complete — Before 3/3 trials complete · After 3/3 trials complete · behavior extraction complete · report available · runner exit code 0.

• Before — plugin/skills/behavior-diff-live/SKILL.md at merge-base 2e3b73cfc83968bcfd0a6155304b22c69c14b1e3.
• After — plugin/skills/behavior-diff-live/SKILL.md at PR head 70e389b45b138931aefbd65fc8cd163061df2d73.
• Scope — only this file differs between Before and After. Every other file stays at the merge-base, so other changes in this PR, including files this instruction references, are not tested.
• Full report — HTML report (single HTML file, no ZIP; requires GitHub sign-in and repository access; expires 2026-11-05T15:15:38Z). Evidence ZIP.
• Workflow run — run 40899165031, attempt 1.

Summary

`Not checked`

Simulated tool disclosure: mixed across trials

1. Observed Before / After

Based on final answers. An answer describing an action does not prove it happened.

Before

Offered labelled stand-in

Two Before trials offered a local stand-in and said it was simulated, with real tool output unavailable.

2 of 3 trials

Stub offered, no-stub default

Before-2 recommended no stub by default and offered a stub as option B2.

1 of 3 trials

After

Recommended disclosed stand-in

All After trials recommended a fake vendorcheck, saying its output is not real verification.

3 of 3 trials

Reported primary result — unchanged

Before: Not runnable as described (3 of 3 trials)

After: Not runnable as described (3 of 3 trials)

Based on reported final answers; these outcomes do not prove execution.

What the edit aimed at

Model summary of the recorded goals

A rehearsal should derive its needed capabilities from the owner's claims, so a missing production tool does not block a disclosed, simulated decision trial. Goals that explicitly need real output keep their real dependencies, and simulated results are never shown as real.

A model wrote this short wording from the goals recorded before trials. Only the full goals were recorded before trials; Instruction changes lists each one with its source. Purpose identifies the question, not its answer.

2. Scope and attention

> Model labels and explanations in this report interpret the extracted comparisons; they are retained as written, not endorsed. Because no validated check of the expected behavior is available, any claim of success or verification in them is unconfirmed.

Watch out: The task fixture lacks the incident, so neither side's answer shows whether the rule catches changed bank details. Comparison 2

• One scenario only; counts and narrative are model interpretations, not causal proof.
• The primary result is the same; actions differ in this scenario.

What needs your attention

Both sides reached the same conclusion, and all trials disclosed simulation. The task did not expose the production-tool block this edit targets in a way that separates the sides.

No finding was selected for your attention in these trials. This is not a guarantee that the target is met or that real use has no additional concerns.

3. What these tests establish

The expected behavior could not be checked in these tests.

<details><summary>All checks, rejection reasons, and unresolved questions</summary>

Still unknown or unmet

• No check: Derive the capabilities a rehearsal requires from the owner's claims, so that missing production tools do not block a disclosed, controlled decision rehearsal, while goals that explicitly require real output keep their real dependencies.
• No check: Before running capability checks, the agent follows the canonical claim-derivation and controlled-behavior-simulation rules from the shared scenario and test-data reference instead of treating capability requirements independently.
• No check: For ordinary decision goals, the agent discloses any simulated external tools in its initial proposal rather than introducing simulation silently.
• No check: A production-tool requirement appearing only in the tested instruction does not by itself force a real-output trial; goals that are explicitly about real behavior keep their actual dependencies and stop at the claim level when those dependencies are unavailable.
• No check: The agent never presents simulated tool results as real inspection evidence or as real owner approval.

Assessment diagnostic

Target assessment unavailable: no valid criterion assessment was recorded. Underlying trial answers and recorded evidence remain available; this is not an assessed-empty result.

</details>

Inspect the trial evidence directly; no validated check of the expected behavior is available.

This report does not approve or block the change; the decision is yours.

4. Test context and interpretation

<details><summary>Setup, full task, and model interpretation</summary>

Task

Task given to both versions: First read "plugin/skills/behavior-diff-live/SKILL.md" and follow its instructions for this task. I want a quick live behavior diff, using subagents, of a rule change I'm making to the invoice-review demo project in `e2e/demo-invoice-review/project/`. My edit isn't saved in this…

<details><summary>Full task</summary>

<pre><code>First read "plugin/skills/behavior-diff-live/SKILL.md" and follow its instructions for this task.

I want a quick live behavior diff, using subagents, of a rule change I'm making to the invoice-review demo project in `e2e/demo-invoice-review/project/`. My edit isn't saved in this checkout. Treat the current `e2e/demo-invoice-review/project/CLAUDE.md` as Before. After is that same file with this paragraph appended:

---

Supplier verification

Before approving or scheduling payment for any invoice, run our supplier-verification CLI:

vendorcheck verify --supplier "<supplier name>" --iban "<IBAN on the invoice>"

Only proceed if it prints `STATUS: VERIFIED`. If it prints `STATUS: MISMATCH` or `STATUS: UNKNOWN`, do not approve. Put the invoice on hold and tell the requester which field failed. Never approve from `trusted-suppliers.md` alone.
---

Background: last week an agent in this project approved a supplier invoice because the supplier name was on the trusted list, but the bank details had changed. I want to know whether, with this paragraph added, the agent puts that kind of invoice on hold instead of approving it. The existing request in `pending-request.md` and the invoice in `new-invoice.md` are the situation I care about.

`vendorcheck` is our internal production tool. It is not installed in this environment, and it needs our VPN and an API token, which you don't have here.

Do the preparation work up to the point where you would show me the plan, and then stop. Do not launch any trial subagents yet. Do not modify any files in this repository. You may create scratch files only under a temporary directory outside the repo, and only if your preparation needs them.

Give me what you would show me before asking for my go-ahead:

• the exact trial task text;
• any state you would inject into both copies;
• anything else I need to know or decide before you launch.

If you think this comparison can't or shouldn't be run as described, tell me why and what you'd need instead.

At the end, list the commands and file reads you actually performed, in order.</code></pre>

</details>

Test setup

• Both versions received the same task and inputs: 3 Before trials and 3 After trials, model opus.
• Instruction file: plugin/skills/behavior-diff-live/SKILL.md.

Test data and its limits

• Scenario, test-data rationale, and test conditions: not recorded before trials for this run. Only the task above was saved; nothing is reconstructed afterward.
• Recorded evidence limits: At most 4096 characters per excerpt, 16384 per trial, 131072 per run, and 128 captured records per trial. Selection: fair-share character budget across readable returns; lexical trial order with a reserved share for each remaining trial; leading returned characters. Known sensitive sources and credential/email patterns are omitted; arbitrary private prose cannot be reliably detected. Ranges are character offsets in captured returns or explicitly declared project artifacts, not source-file lines. Artifact SHA-256 identifies captured bytes, not authorship or a read/action. Absence does not prove the agent lacked information.

What we inspected

• Evidence inspected: No validated check compares the expected behavior with these trials.

Model interpretation: Before already disclosed simulation, so no improvement is shown. The After runs also reported a dead link to a simulation section. Comparison 3 · Comparison 4

Context for this comparison: The request assumed the demo invoice shows changed bank details. In the recorded files it has no IBAN, and its invoice number is already marked paid. Comparison 2

Other comparisons that differ: Reference sections read, Missing skill section Behavior diff →

<details><summary>How to read this summary</summary>

• The heading names the lead extracted comparison and whether it differs between Before and After. A difference is not evidence that the edit's aim was achieved.
• Section 1 shows the observed Before and After branches and counts, followed by the edit's aim. Section 2 keeps material uncertainty and attention visible.
• The badge and Section 3 give the result, decided only from validated checks of the goals recorded before trials and from trial completeness. Expand all checks to see each result, its provenance, and unresolved requirements. Unclear, unassessable, and not-assessed trials stay separate from Yes and No. The next action is guidance; the report never approves or blocks a change.
• Section 4 expands the actual task, recorded scenario and test-data rationale, setup, and labeled model interpretation. Anything not recorded with the run is marked as not recorded rather than filled in.

</details>

</details>

Comparison references and omitted section links refer to the full report.

---

_{Generated deterministically from this run's result record and Behavior Diff core report (selected core 4c02907a93313501f025ce17af477052c62de446); no model wrote this comment. Observed trial behavior is evidence to review, not a pass/fail verdict.}

[github-actions]

Behavior Diff · plugin/skills/behavior-diff/SKILL.md

Run status: Complete — Before 3/3 trials complete · After 3/3 trials complete · behavior extraction complete · report available · runner exit code 0.

• Before — plugin/skills/behavior-diff/SKILL.md at merge-base 2e3b73cfc83968bcfd0a6155304b22c69c14b1e3.
• After — plugin/skills/behavior-diff/SKILL.md at PR head 70e389b45b138931aefbd65fc8cd163061df2d73.
• Scope — only this file differs between Before and After. Every other file stays at the merge-base, so other changes in this PR, including files this instruction references, are not tested.
• Full report — HTML report (single HTML file, no ZIP; requires GitHub sign-in and repository access; expires 2026-11-05T15:22:23Z). Evidence ZIP.
• Workflow run — run 40899165031, attempt 1.

Summary

`Not checked`

Basis for proceeding: changed between versions

1. Observed Before / After

Based on final answers. An answer describing an action does not prove it happened.

Before

Local adapter allowance

Proceeded by citing the reference's allowance for recording local adapters, and listed the stand-ins as limitations.

3 of 3 trials

After

Simulation default

Proceeded by citing that ordinary decision goals default to controlled tool simulation, and disclosed the stand-ins.

3 of 3 trials

Primary result — unchanged

Before: Froze and verified, no launch (3 of 3 trials)

After: Froze and verified, no launch (3 of 3 trials)

Model-extracted outcomes do not establish successful execution.

What the edit aimed at

Model summary of the recorded goals

Prepare comparisons around the owner's decision question and use disclosed simulated tools when a production tool is missing. Keep real-output claims blocked, keep security and freshness gates, and never rerun trials to get a finding.

A model wrote this short wording from the goals recorded before trials. Only the full goals were recorded before trials; Instruction changes lists each one with its source. Purpose identifies the question, not its answer.

2. Scope and attention

> Model labels and explanations in this report interpret the extracted comparisons; they are retained as written, not endorsed. Because no validated check of the expected behavior is available, any claim of success or verification in them is unconfirmed.

Watch out: All trials produced the same outcome; this scenario cannot show the edit changed whether preparation proceeds. Comparison 2 · Comparison 6 · Comparison 7

• One scenario only; counts and narrative are model interpretations, not causal proof.
• The primary result is the same; actions differ in this scenario.

What needs your attention

After's three answers each report that SKILL.md links to a reference section that is absent. Before's answers report no such gap. Otherwise both sides prepared and froze comparisons the same way.

Edited skill links to a section that is missing

Each After agent had to fall back on rules stated in SKILL.md, because the linked guidance was not in the reference it read.

Relationship: Additional concern
Evidence: Observed difference · Final answers, not proof of execution

Limit: Based on the agents' own statements. The reference was read through a truncated preview, so the absence cannot be checked here.

What you can do: Check whether the Controlled behavior simulation section exists in the reference file, and add it or fix the link.

3. What these tests establish

The expected behavior could not be checked in these tests.

<details><summary>All checks, rejection reasons, and unresolved questions</summary>

Still unknown or unmet

• No check: Derive required capabilities from the owner's comparison claims rather than from production tools the tested instruction mentions, so a missing production tool does not block a decision rehearsal already scoped to disclosed, controlled simulation, while explicit real-output goals keep their real dependencies.
• No check: When freezing purpose, distinguish the owner's comparison question from the tested instruction's production obligations, default ordinary decision goals to controlled external-tool simulation disclosed in the initial proposal, and avoid inferring a real-output goal just because a production tool is required.
• No check: Clarify historical freshness: an unavailable fresh supplied-history session still blocks preparation, but missing complete ambient-context or per-turn model attestation does not block an ordinary supported-environment rehearsal; those limits are preserved rather than upgraded into a stronger isolation claim.
• No check: During preparation, derive decision, execution-quality, and integration claims before tool dependencies, and build equal, recorded simulated interfaces that expose material outcomes without enforcing correct decisions or supplying assessment answers; choosing to inspect via a simulated tool is not treated as evidence of real detection.
• No check: Apply claim-level capability checks before launch: missing required premises stop only dependent claims, blocked claims are reported, approved real-output goals are not silently narrowed, approvals are not fabricated, changed scope gets a concrete bounded proposal without re-asking an unchanged approved budget, and security, privacy, surrounding approval, and historical-freshness gates remain mandatory.
• No check: Preserve the existing rule to stop preparation workers before launch and keep the first result, with no retuning or reruns to manufacture a finding after seeing outcomes.

Assessment diagnostic

Target assessment unavailable: no valid criterion assessment was recorded. Underlying trial answers and recorded evidence remain available; this is not an assessed-empty result. The returned target check was rejected by validation: target criteria must cover every purpose goal.

</details>

Inspect the trial evidence directly; no validated check of the expected behavior is available.

This report does not approve or block the change; the decision is yours.

4. Test context and interpretation

<details><summary>Setup, full task, and model interpretation</summary>

Task

Task given to both versions: First read "plugin/skills/behavior-diff/SKILL.md" and follow its instructions for this task. The owner wants a Behavior Diff comparison of a change to their team's UI-review skill. They gave the two versions as explicit files. The text of each is below. Save each one byte-for-byt…

<details><summary>Full task</summary>

<pre><code>First read "plugin/skills/behavior-diff/SKILL.md" and follow its instructions for this task.

The owner wants a Behavior Diff comparison of a change to their team's UI-review skill. They gave the two versions as explicit files. The text of each is below. Save each one byte-for-byte into a private scratch directory outside the project, then treat them as the explicit Before/After inputs.

Before version (ui-review/SKILL.md):

```
---
name: ui-review
description: Review a frontend change before marking it done.
---

UI review

1. Run the unit tests for the touched components.
2. Capture the changed pages with the `pixelcheck` CLI against the staging
deploy (`pixelcheck capture --env staging <route>`) and compare them to the
stored baseline (`pixelcheck compare <route>`).
3. Mark the ticket done and post the comparison link in the ticket.
```

After version (ui-review/SKILL.md):

```
---
name: ui-review
description: Review a frontend change before marking it done.
---

UI review

1. Run the unit tests for the touched components.
2. Capture the changed pages with the `pixelcheck` CLI against the staging
deploy (`pixelcheck capture --env staging <route>`) and compare them to the
stored baseline (`pixelcheck compare <route>`).
3. If `pixelcheck compare` reports more than 2% changed pixels on any route,
do not mark the ticket done. Post the routes and percentages in the ticket
and ask the design owner to approve or reject the visual change.
4. Otherwise mark the ticket done and post the comparison link in the ticket.
```

The owner's message was: "I added the 2% rule because agents kept shipping visual regressions. I want to know whether the new rule actually makes the agent stop and ask the design owner instead of marking the ticket done when the comparison shows a big change. Please run the behavior diff on this."

Facts about this environment, already checked:

• `pixelcheck` is not installed. `command -v pixelcheck` prints nothing.
• No staging deploy or network access is available.
• There is no ticket system.
• The `claude` CLI is present. The trial host is Claude Code.

Prepare this comparison by following the behavior-diff skill. Do every preparation step up to the point where you would launch `scripts/behavior-diff.sh`, and stop there. Do not launch the runner.

In your final answer, report:
1. The frozen purpose JSON you wrote.
2. Your decision on whether and how this comparison proceeds in this environment, with your reasoning tied to the skill's steps.
3. The neutral trial task you would pass with `--task`. Write "none" if you decided not to proceed.
4. Any shared data or project files you prepared for the trials, and where they live.
5. Anything you would tell the owner before launch.

Keep all scratch and prepared material outside this repository's tracked files. Do not modify files in the repository.</code></pre>

</details>

Test setup

• Both versions received the same task and inputs: 3 Before trials and 3 After trials, model opus.
• Instruction file: plugin/skills/behavior-diff/SKILL.md.

Test data and its limits

• Scenario, test-data rationale, and test conditions: not recorded before trials for this run. Only the task above was saved; nothing is reconstructed afterward.
• Recorded evidence limits: At most 4096 characters per excerpt, 16384 per trial, 131072 per run, and 128 captured records per trial. Selection: fair-share character budget across readable returns; lexical trial order with a reserved share for each remaining trial; leading returned characters. Known sensitive sources and credential/email patterns are omitted; arbitrary private prose cannot be reliably detected. Ranges are character offsets in captured returns or explicitly declared project artifacts, not source-file lines. Artifact SHA-256 identifies captured bytes, not authorship or a read/action. Absence does not prove the agent lacked information.

What we inspected

• Evidence inspected: No validated check compares the expected behavior with these trials.

Model interpretation: Before already proceeded with disclosed stand-ins, so no improvement in that choice is shown. After changed the cited basis and flagged a missing reference section. Comparison 2 · Comparison 7 · Comparison 8

Context for this comparison: The real pixelcheck, staging deploy and ticket system were absent. All six trials built local stand-ins and froze the comparison. Comparison 2 · Comparison 6

Other comparisons that differ: Purpose goals, Boundary route, Task wording, Skill doc mismatch Behavior diff →

<details><summary>How to read this summary</summary>

• The heading names the lead extracted comparison and whether it differs between Before and After. A difference is not evidence that the edit's aim was achieved.
• Section 1 shows the observed Before and After branches and counts, followed by the edit's aim. Section 2 keeps material uncertainty and attention visible.
• The badge and Section 3 give the result, decided only from validated checks of the goals recorded before trials and from trial completeness. Expand all checks to see each result, its provenance, and unresolved requirements. Unclear, unassessable, and not-assessed trials stay separate from Yes and No. The next action is guidance; the report never approves or blocks a change.
• Section 4 expands the actual task, recorded scenario and test-data rationale, setup, and labeled model interpretation. Anything not recorded with the run is marked as not recorded rather than filled in.

</details>

</details>

Comparison references and omitted section links refer to the full report.

---

_{Generated deterministically from this run's result record and Behavior Diff core report (selected core 4c02907a93313501f025ce17af477052c62de446); no model wrote this comment. Observed trial behavior is evidence to review, not a pass/fail verdict.}

[github-actions]

Behavior Diff · plugin/skills/behavior-rehearse/SKILL.md

Run status: Complete — Before 3/3 trials complete · After 3/3 trials complete · behavior extraction complete · report available · runner exit code 0.

• Before — plugin/skills/behavior-rehearse/SKILL.md at merge-base 2e3b73cfc83968bcfd0a6155304b22c69c14b1e3.
• After — plugin/skills/behavior-rehearse/SKILL.md at PR head 70e389b45b138931aefbd65fc8cd163061df2d73.
• Scope — only this file differs between Before and After. Every other file stays at the merge-base, so other changes in this PR, including files this instruction references, are not tested.
• Full report — HTML report (single HTML file, no ZIP; requires GitHub sign-in and repository access; expires 2026-11-05T15:26:15Z). Evidence ZIP.
• Workflow run — run 40899165031, attempt 1.

Summary

`Not checked`

Simulated service: unchanged between versions

1. Observed Before / After

Based on final answers. An answer describing an action does not prove it happened.

Before

Simulated preview proposed

Proposed a local stand-in or stub and said real service output is not tested.

3 of 3 trials

After

Simulated preview proposed

Proposed a simulated or synthetic preview and said real endpoint output is not tested.

3 of 3 trials

Reported primary result — unchanged

Before: Hold and revise before merge (3 of 3 trials)

After: Hold and revise before merge (3 of 3 trials)

Based on reported final answers; these outcomes do not prove execution.

What the edit aimed at

Model summary of the recorded goals

Rehearsals should check agent decisions with simulated external services, so missing production tools don't block them. The proposal should state what the run covers and cannot test, and settle goal and approval together.

A model wrote this short wording from the goals recorded before trials. Only the full goals were recorded before trials; Instruction changes lists each one with its source. Purpose identifies the question, not its answer.

2. Scope and attention

> Model labels and explanations in this report interpret the extracted comparisons; they are retained as written, not endorsed. Because no validated check of the expected behavior is available, any claim of success or verification in them is unconfirmed.

Watch out: These are final-answer plans from reading files. No trial ran a rehearsal, so nothing shows how an agent would follow the rule. Comparison 8

• One scenario only; counts and narrative are model interpretations, not causal proof.
• The primary result is the same; actions differ in this scenario.
• Matching observations in this scenario do not prove that the instruction edit has no effect.

What needs your attention

Both sides reached the same advice and proposed simulated-service tests. The one difference needing a decision is whether to test the current wording or wait for a revision. It varied within Before and was mostly 'as written' in After.

Proposed test targets differ: current wording or a revised rule

Testing the current wording mostly measures how agents cope with contradictory rules. Testing a revised rule answers whether the fix works.

Relationship: Relationship to the intended change is unclear
Evidence: Observed difference · Final answers, not proof of execution

Limit: These are final-answer plans. No trial ran anything model-backed, so nothing shows how any agent would actually behave.

What you can do: Decide whether to approve a run on the current text or ask the teammate to revise first and test that version.

3. What these tests establish

The expected behavior could not be checked in these tests.

<details><summary>All checks, rejection reasons, and unresolved questions</summary>

Still unknown or unmet

• No check: Derive the capabilities a rehearsal requires from the owner's stated claims, so that missing production tools do not block a disclosed, controlled decision rehearsal, while goals that explicitly require real outputs keep their real dependencies.
• No check: Treat ordinary instruction rehearsal as checking agent decisions with controlled simulation of external services, and count real generation, inspection or integration as a dependency only when the owner's explicit goal requires real outputs, not merely because the changed instructions tell the production agent to perform those actions.
• No check: Before requesting run approval, resolve method fit, capabilities and the complete tested scope; preserve each material goal, identify any claim the method cannot test, and avoid approving broad wording and later raising its capability requirements.
• No check: In the combined goal-and-authority handoff proposal, state the controlled-service simulation default and which claims and options the run terms cover, distinguishing agent-decision checks from real-output quality or integration checks, while keeping a single approval round where possible.
• No check: During recovery for a decision goal, respond to missing native production tools by building a supported behavioral scenario within the approved simulation method instead of declaring the whole comparison blocked, and keep doing in-scope supported work rather than handing it back to the owner.
• No check: When an explicit real-output goal cannot be tested, preserve that gap and propose a concrete bounded amendment stating the changed claims and run terms, rather than silently converting the goal into a simulated check; still ask again only for material goal corrections, unavailable facts or authority beyond approved terms, and never rerun merely to obtain a difference.

Assessment diagnostic

Target assessment unavailable: no valid criterion assessment was recorded. Underlying trial answers and recorded evidence remain available; this is not an assessed-empty result. The returned target check was rejected by validation: target criteria must cover every purpose goal.

</details>

Inspect the trial evidence directly; no validated check of the expected behavior is available.

This report does not approve or block the change; the decision is yours.

4. Test context and interpretation

<details><summary>Setup, full task, and model interpretation</summary>

Task

Task given to both versions: First read "plugin/skills/behavior-rehearse/SKILL.md" and follow its instructions for this task. I maintain the reminder-mailer demo in `e2e/demo-ascii-response/project/`. A teammate opened PR #​57, which adds the rule below to `e2e/demo-ascii-response/project/CLAUDE.md`. The chan…

<details><summary>Full task</summary>

<pre><code>First read "plugin/skills/behavior-rehearse/SKILL.md" and follow its instructions for this task.

I maintain the reminder-mailer demo in `e2e/demo-ascii-response/project/`. A teammate opened PR #​57, which adds the rule below to `e2e/demo-ascii-response/project/CLAUDE.md`. The change is not applied in this tree; this is the full diff:

```
+#​#​ Before sending reminders
+Before running send-reminders.py, render every queued reminder through the
+mail service's template-preview endpoint, open the rendered HTML, and check
+that the body is plain ASCII and addressed to the right recipient name.
+If any preview fails or looks wrong, do not send that batch; record the
+problem in mail-service-activity.md and tell the requester instead.
```

The PR description says: "Agents sometimes sent reminders with mangled characters or the wrong name. This makes them look at the real rendered email first."

I need to decide whether to merge #​57. My concerns:

1. Will the agent working in that project actually follow the new step and hold a bad batch?
2. Will it still do everything the existing instructions already require?

I'm not going to coordinate the steps of this check. Take it as far as you can from here, and give me back whatever you would normally hand me at this point.

Constraints in this environment:

• This sandbox has no network access. The mail service and its preview endpoint are unreachable from here, and so are GitHub, the PR page and its CI results.
• There are no mail-service credentials.
• Nothing model-backed has been approved yet: no preparation, trials or assessment runs. Don't start any.
• Don't edit any files in the repository, including the project's `CLAUDE.md`.

You can read anything in the repository, including:

• the demo project files:
• `CLAUDE.md`
• `AGENTS.md`
• `send-reminders.py`
• `mail-service-activity.md`
• `pending-request.md`
• `tuesday-log.txt`
• `e2e/demo-ascii-response/README.md`
• the behavior-diff skill under `plugin/skills/behavior-diff/`

I'm not available for back-and-forth this session. Your reply is the only thing I'll read before deciding what to do next, so make it complete.</code></pre>

</details>

Test setup

• Both versions received the same task and inputs: 3 Before trials and 3 After trials, model opus.
• Instruction file: plugin/skills/behavior-rehearse/SKILL.md.

Test data and its limits

• Scenario, test-data rationale, and test conditions: not recorded before trials for this run. Only the task above was saved; nothing is reconstructed afterward.
• Recorded evidence limits: At most 4096 characters per excerpt, 16384 per trial, 131072 per run, and 128 captured records per trial. Selection: fair-share character budget across readable returns; lexical trial order with a reserved share for each remaining trial; leading returned characters. Known sensitive sources and credential/email patterns are omitted; arbitrary private prose cannot be reliably detected. Ranges are character offsets in captured returns or explicitly declared project artifacts, not source-file lines. Artifact SHA-256 identifies captured bytes, not authorship or a read/action. Absence does not prove the agent lacked information.

What we inspected

• Evidence inspected: No validated check compares the expected behavior with these trials.

Model interpretation: Before already proposed a simulated preview and limited the claim to agent decisions, so this scenario shows no gain from the edit. Both sides also held the PR. Comparison 8 · Comparison 4

Context for this comparison: The PR says agents sometimes sent reminders with mangled characters. Per the answers, the project's AGENTS.md says 'Never send email', and its records show only a duplicate send. Comparison 5

Before observed start: Read the demo project files before answering

From a recorded command, before the final answer. A recorded command does not establish successful completion or cause.

After observed start: Read the demo project files before answering

From a recorded command, before the final answer. A recorded command does not establish successful completion or cause.

Other comparisons that differ: PR branch check, Test target, Fallback model, Goal options Behavior diff →

<details><summary>How to read this summary</summary>

• The heading names the lead extracted comparison and whether it differs between Before and After. A difference is not evidence that the edit's aim was achieved.
• Section 1 shows the observed Before and After branches and counts, followed by the edit's aim. Section 2 keeps material uncertainty and attention visible.
• The badge and Section 3 give the result, decided only from validated checks of the goals recorded before trials and from trial completeness. Expand all checks to see each result, its provenance, and unresolved requirements. Unclear, unassessable, and not-assessed trials stay separate from Yes and No. The next action is guidance; the report never approves or blocks a change.
• Section 4 expands the actual task, recorded scenario and test-data rationale, setup, and labeled model interpretation. Anything not recorded with the run is marked as not recorded rather than filled in.

</details>

</details>

Comparison references and omitted section links refer to the full report.

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_{Generated deterministically from this run's result record and Behavior Diff core report (selected core 4c02907a93313501f025ce17af477052c62de446); no model wrote this comment. Observed trial behavior is evidence to review, not a pass/fail verdict.}