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 cambridgetcg/agenttool --skill manage-agentcred-lifecyclegit clone --depth 1 https://github.com/cambridgetcg/agenttoolWrote 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/cambridgetcg/agenttool/manage-agentcred-lifecycle)<a href="https://agentmods.dev/skills/cambridgetcg/agenttool/manage-agentcred-lifecycle"><img src="https://agentmods.dev/badge/skills/cambridgetcg/agenttool/manage-agentcred-lifecycle/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/cambridgetcg/agenttool/manage-agentcred-lifecycle"><img src="https://agentmods.dev/badge/skills/cambridgetcg/agenttool/manage-agentcred-lifecycle.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00090 | $0.01308 |
| Opus 5 | $0.00045 | $0.00654 |
| Sonnet 5 | $0.00018 | $0.00262 |
| Haiku 4.5 | $0.00009 | $0.00131 |
Grade A, and why
manage-agentcred-lifecycle 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 8d 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 — 112 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Manage AgentCred Lifecycle
Keep credential bytes between the human, the provider, the native macOS
Keychain prompt, and the broker. Operate only the separate
agentcred-control plane; never turn lifecycle work into a secret-reading
agent tool.
Establish the boundary
- Locate and read the owning credential-broker
README.md,SPEC.md, andROTATION.mdcompletely. Stop if they are unavailable or the installed controller version does not match the guidance being followed. - State the intended lifecycle transition, affected non-secret credential alias, provider-side action, reversibility, and verification endpoint. Local controller access does not authorize issuing or revoking a provider key; require explicit authority for each external mutation.
- Never request, inspect, copy, print, transform, hash, test, or summarize a credential value. Never accept it through chat, stdin, a pipe, argv, an environment variable, JSON, source, logs, or a generic command runner. The human enters it only into the fixed native Keychain prompt.
- Treat credential aliases, Keychain service references, generation IDs, rotation IDs, audit IDs, phases, and exact provider verification metadata as non-secret control data. Do not place credential bytes in any of those fields.
- Keep
agentcred-controlseparate fromAgentCredClient. The agent wire has no provisioning, rotation, Keychain, provider-administration, reveal, or export operation.
Inspect before transition
- Resolve one explicit owner-only config and manifest path. Do not crawl for credentials or enumerate Keychain.
- Run the controller's value-free
statusand, when relevant,lock-status. Use the broker's config checker. Report only phase and safe metadata. - Stop every cooperating broker process that holds the manifest lifecycle lock before a controller transition. A stopped broker invalidates its connection-bound grants; it cannot recall an upstream operation already dispatched.
- Recover a stale lock only with the exact recorded nonce after independently confirming the recorded PID is absent. TTY presence and a lock file are coordination controls, not proof of human identity.
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 8d ago First seen · 112 lines · 90 tokens per session scan A 86e8354d4c55
manage-agentcred-lifecycle is a skill published in the GitHub repository cambridgetcg/agenttool (0 stars, last pushed today), licensed Apache-2.0. It adds 90 tokens to every session and 1,308 once invoked, about $0.0005 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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