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 skills add spences10/my-pi --skill execute-harnessgit clone --depth 1 https://github.com/spences10/my-piWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/spences10/my-pi/execute-harness)<a href="https://agentmods.dev/skills/spences10/my-pi/execute-harness"><img src="https://agentmods.dev/badge/skills/spences10/my-pi/execute-harness/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/spences10/my-pi/execute-harness"><img src="https://agentmods.dev/badge/skills/spences10/my-pi/execute-harness.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00032 | $0.00841 |
| Opus 5.5 | $0.00013 | $0.00336 |
| Sonnet 5.5 | $0.00006 | $0.00168 |
| Haiku 4.5 | $0.00003 | $0.00084 |
Grade A, and why
execute-harness 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 75 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Execute Harness
Run the task through an existing my-pi harness. Its outer policy is the runtime trust boundary; its versioned inner scaffold is an amendable execution plan subordinate to system, developer, and current user instructions.
Workflow
- Resolve the harness directory from the user request or active harness context.
- Read
harness.json,SYSTEM.md,TASK.md, andstatus.jsonbefore editing. - Call
harness_updatewithstatus: runningand the current phase. - If the
teamtool is available and you are the team lead, create or reuse a team, create/claim a task for the harness, and use onemember_spawnexecutor withmutating: truefor file-editing work. Default to the contractcwd; useworkspace_mode: worktreeonly when the user asks for isolation or the plan covers setup, runtime state, merge, and cleanup ownership. - The teammate prompt must tell it to read
harness.json,SYSTEM.md,TASK.md, andstatus.json, execute only inside the contract, runvalidate.shandreview.sh, update harness evidence, and report changed files plus risks. If using a worktree, setHARNESS_CWDto that worktree for validation and review. - Recover any remaining source-of-truth context needed to act safely.
- Execute surgically inside
scaffold.allowed_paths. Useharness_amendfor a bounded change inside the approved capability. If user direction or source evidence introduces a new capability, architecture decision, or outer-policy expansion, stop execution and enter assessment instead of silently expanding the harness. An approved harness recommendation may then amend the active scaffold. - Record decisions, phase changes, and validation evidence with
harness_update, including team status and remaining risks when known. - Run
<harness_dir>/validate.sh. - Run
<harness_dir>/review.shfrom the execution workspace. If using a linked worktree, run it from that worktree or setHARNESS_CWDto the worktree path. - Review
<harness_dir>/OUTCOME.mdor<harness_dir>/outcome.jsonfor changed files, baseline ignored files, validation evidence, team status, and risks. - Mark
completedonly when validation passes and no escalation rule applies; otherwise markfailedwith evidence. A terminal status seals the run and keeps its guard active for the remainder of the current turn. The extension deactivates it on the next direct user turn or session startup.
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.
- 1mo ago First seen · 75 lines · 32 tokens per session scan A a796049c3224
execute-harness is a skill published in the GitHub repository spences10/my-pi (137 stars, last pushed today), licensed MIT. It adds 32 tokens to every session and 841 once invoked, about $0.0001 per session on Opus 5.5. 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.
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