Borrowing it
Nothing to install: this file belongs to MilindGaharwar/fettle. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/MilindGaharwar/fettle/main/.github/prompts/fettle-mcp-revoke.prompt.mdgit clone --depth 1 https://github.com/MilindGaharwar/fettleWrote 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/commands/milindgaharwar/fettle/fettle-mcp-revoke)<a href="https://agentmods.dev/commands/milindgaharwar/fettle/fettle-mcp-revoke"><img src="https://agentmods.dev/badge/commands/milindgaharwar/fettle/fettle-mcp-revoke/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/commands/milindgaharwar/fettle/fettle-mcp-revoke"><img src="https://agentmods.dev/badge/commands/milindgaharwar/fettle/fettle-mcp-revoke.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 | $0.00019 | $0.00414 |
| Opus 5 | $0.00010 | $0.00207 |
| Sonnet 5 | $0.00004 | $0.00083 |
| Haiku 4.5 | $0.00002 | $0.00041 |
Grade B, and why
fettle-mcp-revoke scanned grade B with 1 finding 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 today.
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.
Asks for rootmediumPrivilege escalation
A mod that escalates privileges can change anything on the machine, not only the project.
- Writes to a temp file then sudo copies it to the ledger path Copies of this mod
1 near-identical copy found in the catalogue:
- mcp-revoke — 88% identical, 9 lines differ
What it actually says
$ARGUMENTS refers to any text the user typed after the slash command.
Remove a package from the root-owned allowlist ledger.
Procedure
-
Parse arguments. Extract package name from $ARGUMENTS (e.g.,
@playwright/mcp). -
Locate and check the ledger. The allowlist lives at
~/.config/fettle/mcp-allowlist.jsonby default (a policy-pinned[gates.mcp_trust].allowlist_pathwins; otherwise theMCP_ALLOWLIST_PATHenv var). Read it and verify the package exists underpackages. If not found, report and stop. -
Show current entry. Display the package's version, audit date, auditor, and report path.
-
Confirm with human. Ask: "Are you sure you want to revoke from the allowlist? This will block all future installations and executions."
-
If confirmed, remove from ledger via sudo. Use a Python script that:
- Reads the current allowlist ledger
- Removes the package entry from the packages dict
- Writes to a temp file then sudo copies it to the ledger path
- Sets ownership to root:root and permissions to 0644
-
Confirm the ledger was updated by reading it back and verifying the package is no longer listed.
-
Report what was removed and remind the user that:
- Any installed instance of this package will still exist on disk
- Future attempts to install or execute it will be blocked by all 3 layers
- To fully remove it, also uninstall the package manually
Rules
- NEVER revoke without explicit human confirmation in the conversation.
- Always show what is being removed before asking for confirmation.
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.
- today Changed · +2 lines · +7 tokens per session 5ae8c053ec3d
- 9d ago First seen · 36 lines · 12 tokens per session scan B 1afb11147547
fettle-mcp-revoke is a command published in the GitHub repository MilindGaharwar/fettle (4 stars, last pushed yesterday), licensed Apache-2.0. It adds 19 tokens to every session and 414 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it B with 1 finding (asks for root). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other commands, from other repositories
scout-scan
Scan a path with Scout and walk through the security findings.
kb-ingest
Ingest external material into Sources/ inside the bound project KB, then update registry, index, and daily note as needed.
atomic-plan
Write a design doc (concepts, business rules, approaches) and a checkpoint-table spec (contract) for non-trivial work; inline spec only for trivial. Gauges triviality; loops spec authoring with subagents. Human-facing artifact, Mermaid diagrams allowed.
session-report
Capture what changed this session and why, scoped to the current branch. Read by ship verbs when synthesizing the commit message; deleted after a successful commit.
afo
Open feature worktree in terminal and start agent (shortcut for feature-open).
ai-review
AI code review of the staged git diff via the Claude API.