JustSAFE
mcp server for just
Overview
From the repository's own README, as read at the audited commit. Badges and raw HTML are left out.
[](https://github.com/PromptExecution/just-mcp/actions/workflows/ci.yml) [](https://github.com/PromptExecution/just-mcp/actions/workflows/release.yml) [](https://crates.io/crates/just-mcp) [](https://opensource.org/licenses/MIT)
[](https://archestra.ai/mcp-catalog/promptexecution__just-mcp)
👋 A way to let LLMs speak Just
A production-ready MCP server that provides seamless integration with Just command runner, enabling AI assistants to discover, execute, and introspect Justfile recipes through the standardized MCP protocol.
🎯 Why Just + MCP = Better Agent Execution
Context-Saving Abstraction
If it isn't immediately obvious, the benefit of having LLMs use Just vs. bash is that running Just commands (via MCP) provides a context-saving abstraction where they don't need to waste context opening/reading bash files, Python scripts, or other build artifacts. The LLM via MCP simply gets the command, parameters, and hints - it's in their memory as "these are commands available to you."
Eliminates the Justfile Learning Curve
No more watching LLMs execute just -l to get command lists, inevitably start reading the justfile, then try to write justfile syntax (like it's a Makefile), corrupt the justfile, and create a bad experience. Just's evolving syntax simply doesn't have a large enough corpus in frontier models today - we need more popular repos with justfiles in the training dataset.
Safer Than Raw Bash Access
Just-mcp is fundamentally safer than bash. If you read HackerNews, there's a story at lea
69121b198deeOBSERVED · 2026-10-08Connect
Built from this server's own package name, version and transport as found in its source — not copied from anyone's documentation, so it cannot drift against a page we do not control.
claude mcp add just-mcp:0.1.5 -- docker run -i --rm ghcr.io/promptexecution/just-mcp:0.1.5:None
Trust audit
SAFEgrade B · trust 89/100 Nothing in the source contradicts what it says it does. Grade A is reserved for packages that have also passed the behavioural sandbox.
| Layer | What it checks | Result |
|---|---|---|
| L0 | Provenance & inventory | PASS |
| L1 | Static analysis of the code | PASS |
| L2 | Instruction surface (what it tells the agent) | PASS |
| L3 | Class-specific surface | PASS |
| L4 | Behavioural (sandbox) | SKIPPED |
What the source does
- Filesystem
- declared (1 observation(s))
- Network
- declared (3 observation(s))
- Shell
- declared (3 observation(s))
- Dependencies
- pinned
- Secrets in source
- none-found
Findings (9)
.b00tignore
.rooignore
.roomodes
.windsurfrules
AGENTS 2.md
AGENTS.md
tar czf ../../../${{ matrix.archive_name }} ${{ matrix.artifact_name }}tar czf ../../../${{ matrix.archive_name }} ${{ matrix.artifact_name }}Gates applied: no_behavioural_pass.
69121b198deefull audit observations/trust-audit/mcp-server/promptexecution__just-1.json · Report an issue / request a re-scanAudit history
Every audit this server has had. A grade with a past is a grade somebody is still checking.
| Date | Source | Verdict | Grade | Score | Change |
|---|---|---|---|---|---|
| 2026-10-08 | 69121b198dee | SAFE | B | 89 | first audit |
Questions
What is the Just MCP server?
mcp server for just
Is Just safe to connect to an agent?
The audit found nothing in the source that contradicts what it says it does, and graded it B (89/100). Grade A is held back for packages that have also passed a sandboxed behavioural run, which is why a clean server reads B.
What credentials does Just need?
No credential environment variables were found in its source, so it appears to need none.
How does Just run?
It speaks stdio, so it runs as a local process your client starts. It is published on npm as just-mcp at 0.1.0.
How current is this page?
The grade is for one exact copy of the source (69121b198dee), read on 2026-10-08. The repository is watched and re-audited when it changes.