proof-capture

A command that records evidence for a feature, such as screenshots, video, and written proof, for inclusion in a pull request. A pull request is a proposed code change submitted for review.

In plain words
What is it for?
Use it to rehearse a test flow, record its steps, assert expected results, validate the recording, and generate PROOF.md and PR-BODY.md files.
Why use it?
It provides a controlled record that the feature was tested and validates the captured evidence before finalizing it.

Command

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add commands/lykhoyda/rn-dev-agent/proof-capture
Clone the repo
git clone --depth 1 https://github.com/Lykhoyda/rn-dev-agent
Per session 21 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 945 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00021 $0.00945
Opus 5 $0.00010 $0.00473
Sonnet 5 $0.00004 $0.00189
Haiku 4.5 $0.00002 $0.00094

Measured yesterday against content hash da0650fc7ca8, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

proof-capture scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

packages/claude-plugin/commands/proof-capture.md · 85 lines

How it starts

The opening of the file, as written. The whole thing — 85 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Capture PR proof artifacts for: $ARGUMENTS

If $ARGUMENTS contains --strict, execute the strict controller workflow below. Otherwise, load the capturing-proof skill and execute its Protocol (Steps 1–9) inline in this parent session. Use the first argument as <feature-slug> (ask the user if missing) and the remaining arguments as the flow description. The skill owns the interactive rehearsal gate, named Maestro-inexpressibility carve-out, validation checklist, PROOF.md, and PR-BODY.md generation; do not duplicate or improvise that protocol here.

Strict controller workflow

Call proof_capture(action="contract") first and retain the returned schema and digest as the receipt contract. The transition protocol is:

begin_rehearsal -> finish_rehearsal -> arm -> start_recording
  -> storyboard operations and proof_step assertions
  -> stop_recording -> validate -> finalize

Before begin_rehearsal, resolve and pass the complete immutable context:

  • clean absolute Git project root and candidate root
  • unique lowercase kebab-case run id
  • fresh absolute receipt, video, contact-sheet, and screenshot paths beneath docs/proof/<run-id>/
  • issue identity, exact pull-request head SHA, proof class, acceptance mappings, fixture identity, and writer provider
  • one learned action with its id, runtime revision, and exact action-file SHA-256
  • at least three ordered storyboard steps whose source SHA equals clean HEAD
  • for every step, canonical operation arguments and hash, exact proof_step arguments and hash, verifyTestID, screenshot path, and a bounded assertionWaitMs

When the driven app is outside this plugin repository, candidateRoot is mandatory and must identify the exact candidate checkout. Any candidate SHA, packaged runtime, runner manifest, live MCP process, project root, Metro session, port, device, or build-output mismatch is a hard stop.

Execute the transitions exactly:

  1. Call begin_rehearsal with the immutable context.
  2. Call only cdp_run_action(autoRepair=false, forceReload=false, proofReplay=true) during rehearsal, then call finish_rehearsal.
  3. Restore the declared start state, run its exact proof_step, call arm, and repeat that assertion.
  4. Call start_recording; never call device_record directly.
  5. Execute each storyboard operation once in order and immediately follow it with its declared proof_step. Do not add undeclared tools.
  6. Call stop_recording, then validate.
  7. Give the mechanically accepted receipt and contact sheet to a vision-capable reviewer whose provider differs from the writer. The review must bind writerProvider, evidenceSha256, resultHash, and the exact boolean verdicts required by the receipt schema.
  8. Call finalize(evidenceReview=...) and report only values from the accepted finalized receipt.

The controller requires managed Metro ownership, a serving root contained by the bound worktree, a signed initial-bundle marker, exact device and install bindings, and the source and dirty digest. Darwin receipts report managed-sandbox-v1 when the Apple-signed absolute-path Seatbelt sandbox and command-chain change detection are available; other hosts report unavailable. The sandbox level is evidence, not a strict-proof precondition. Do not record before the controller permits it, substitute screenshots for the required video, repair or reload during rehearsal or recording, reuse rejected artifacts, or report merge-ready evidence without a finalized accepted receipt.

When stage is uncertain, call status. On rejection, print the stable reason code exactly, call discard, restore the clean start state, and begin a fresh session with fresh destinations. Strict output contains only the accepted receipt path, screenshot paths, local video path and SHA-256, contact-sheet path, action and storyboard hashes, or the exact invalidation reason.

Read the full file on GitHub · 85 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 85 lines · 0 tokens per session scan A da0650fc7ca8

Subscribe to this mod's changes

proof-capture is a command published in the GitHub repository Lykhoyda/rn-dev-agent (11 stars, last pushed yesterday), licensed MIT. It adds 21 tokens to every session and 945 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.