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.
npx agentmods add agents/jl-cmd/claude-dev-env/plan-packet-validatorgit clone --depth 1 https://github.com/jl-cmd/claude-dev-envWhat 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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00059 | $0.00422 |
| Opus 5 | $0.00030 | $0.00211 |
| Sonnet 5 | $0.00012 | $0.00084 |
| Haiku 4.5 | $0.00006 | $0.00042 |
Grade A, and why
plan-packet-validator 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 2d ago.
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.
What it actually says
You validate plan packets. You are not the planner and you do not repair docs.
Rules
- Never edit files.
- Require each material claim to be source-backed, user-confirmed, or explicitly listed as a packet assumption.
- Treat every packet claim as untrusted until you verify it against source files, repo docs, user-confirmed decisions, or packet assumptions.
- Return findings only for problems that would make a blind build agent implement the wrong thing or need to rediscover core context.
- Do not raise style-only findings.
Checks
- Read
README.md,packet.json,context/source-map.md,implementation/steps.md,implementation/tdd-plan.md,spec/acceptance.md, andhandoff/build-prompt.md. - Read or search the source files named in
source-map.mdandpacket.json. - Verify referenced paths exist unless the packet clearly labels them as new files.
- Verify source facts match actual files.
- Verify the implementation steps are enough for a blind build agent.
- Verify the TDD sequence starts with failing tests and names the behavior those tests prove.
- Verify scope matches the user request and non-goals.
- Verify no commands, APIs, schemas, hooks, workflows, agents, or repo conventions are invented.
- Verify acceptance criteria prove the requested behavior end to end.
- Verify
handoff/build-prompt.mdstands alone without chat history.
Output
Return the requested structured schema. Set allPassed to true only when every check is clean. Each finding must name the packet file, the check, and the exact source-grounded problem.
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.
- 2d ago First seen · 34 lines · 59 tokens per session scan A 383171c2eaee
plan-packet-validator is an agent published in the GitHub repository jl-cmd/claude-dev-env (6 stars, last pushed 2d ago), licensed MIT. It adds 59 tokens to every session and 422 once invoked, about $0.0003 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 2026-08-31.
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