Agent Mail

Advisory file reservations and messaging to coordinate multiple agents writing one repo

Works with setup

Test report

Verdict
Works with setup
Score
7.6/10
Tested
Jul 21, 2026
Environment
Claude Code 2.x (agent harness)
Upstream re-checked
Aug 10, 2026 · 6c2b938

⚠ The author changed this skill after we tested it. The verdict below describes the version we ran on Jul 21, 2026; it's queued for a re-test.

Located SKILL.md at skills/agent-mail/SKILL.md (mirrored in skills-codex/ and images/gemini/skills/). Frontmatter parses with name+description; all three referenced files (references/TOOLS.md, WORKFLOWS.md, RECOVERY.md) returned HTTP 200; paths are relative with no hardcoded machine paths. No security smells (no curl|sh, base64, or exfiltration); it describes a destructive `clear-and-reset-everything` and a git pre-commit guard but gates both behind explicit per-operation caller authorization. TRIGGER: I judged 5 phrasings — SHOULD: "coordinate two agents editing the same repo so they don't clobber files", "reserve src/auth/** while I refactor so the other writer stays off it", "set up file reservations for our multi-agent session"; should NOT: "email my client about the invoice", "reserve a conference room for the team meeting" — all 5 decided correctly (the description clearly scopes it to agent-to-agent coordination, not real mail). OUTPUT unmeasurable: the skill is a thin adapter whose every action requires the Agent Mail MCP tools or an `am` CLI, and `which am` returned not found with no MCP present; I could only fabricate ids/reservations, which would not honestly measure the skill. DOCS solid and refreshingly non-overselling (explicit "does not do" boundary, named failure modes), docked 1 point because nothing in the skill or its references tells you how to obtain/install the backend the whole skill depends on. Note: frontmatter sets user-invocable:false (meant to be consumed by the agent-native skill), so a human won't invoke it directly.

Scored on four weighted criteria — install, triggering, output vs. baseline, docs. How scoring works

  • Installs cleanly 5/5
  • Triggers reliably 5/5
  • Output vs. baseline 5/10
  • Docs & honesty 4/5

What Agent Mail does

Agent Mail is a Claude/Codex skill that acts as an adapter over an external "Agent Mail" backend (MCP tools or an `am` CLI) for coordinating multiple agents writing to the same repository. It registers agent identities, sends threaded messages/acknowledgements, and places advisory, TTL-bounded file reservations so cooperating writers avoid clobbering each other's paths. It triggers on multi-agent coordination requests like "coordinate writers" or "reserve files".

How to install Agent Mail

git clone --depth 1 https://github.com/boshu2/agentops.git /tmp/agent-mail-src
mkdir -p ~/.claude/skills
cp -R /tmp/agent-mail-src/skills/agent-mail ~/.claude/skills/agent-mail
# REQUIRES an external "Agent Mail" backend that is NOT installed by the copy above:
# either the Agent Mail MCP tools (ensure_project, register_agent, send_message,
# file_reservation_paths, ...) registered in your client, OR a self-describing `am` CLI
# on PATH (discover syntax via `am mail --help`, `am file_reservations --help`).
# Neither ships in this skill folder; the skill only orchestrates them. Without one of
# them present the skill's own "Adapter unavailable" branch says to stop.
# `am`/agentops CLI appears to live in the repo's cli/ (Go); building/running it plus its
# datastore is a separate setup step not covered by the skill files.

Skills live in ~/.claude/skills/ (global) or .claude/skills/ (per-project). Restart Claude Code after installing.

Commands — how to trigger Agent Mail

  • /agent-mail Advisory file reservations and messaging to coordinate multiple agents writing one repo

It also activates on plain-language prompts like these:

  • Coordinate these two agents using Agent Mail
  • Set up a lock so agents don't collide on this file
  • Hand off this task to another agent via inbox

Frequently asked questions

Is the Agent Mail skill free?
Yes. The skill itself is free from boshu2/agentops. SkillProof publishes the install command and an independent test verdict at no cost.
Does Agent Mail work with Claude Code?
We tested it with Claude Code 2.x (agent harness) on Jul 21, 2026. Verdict: Works with setup. Located SKILL.md at skills/agent-mail/SKILL.md (mirrored in skills-codex/ and images/gemini/skills/). Frontmatter parses with name+description; all three referenced files (references/TOOLS.md, WORKFLOWS.md, RECOVERY.md) returned HTTP 200; paths are relative with no hardcoded machine paths. No security smells (no curl|sh, base64, or exfiltration); it describes a destructive `clear-and-reset-everything` and a git pre-commit guard but gates both behind explicit per-operation caller authorization. TRIGGER: I judged 5 phrasings — SHOULD: "coordinate two agents editing the same repo so they don't clobber files", "reserve src/auth/** while I refactor so the other writer stays off it", "set up file reservations for our multi-agent session"; should NOT: "email my client about the invoice", "reserve a conference room for the team meeting" — all 5 decided correctly (the description clearly scopes it to agent-to-agent coordination, not real mail). OUTPUT unmeasurable: the skill is a thin adapter whose every action requires the Agent Mail MCP tools or an `am` CLI, and `which am` returned not found with no MCP present; I could only fabricate ids/reservations, which would not honestly measure the skill. DOCS solid and refreshingly non-overselling (explicit "does not do" boundary, named failure modes), docked 1 point because nothing in the skill or its references tells you how to obtain/install the backend the whole skill depends on. Note: frontmatter sets user-invocable:false (meant to be consumed by the agent-native skill), so a human won't invoke it directly.
What is the Agent Mail SkillProof Score?
7.6/10 — installs cleanly 5/5, triggers reliably 5/5, output vs. baseline 5/10, docs & honesty 4/5.
How do I install Agent Mail?
Copy the install command from this page, run it in your terminal, and restart Claude Code. Skills live in ~/.claude/skills/ (global) or .claude/skills/ inside a project.
Can I use Agent Mail with Cursor, Copilot, Gemini CLI, Codex or other AI tools?
The SKILL.md format is native to Claude (Claude Code, Desktop, claude.ai). The instructions inside adapt to other assistants: Cursor rules, GitHub Copilot instructions, Windsurf rules, Custom GPTs, AGENTS.md for OpenAI Codex, and GEMINI.md for Google Gemini CLI — our conversion guides cover each, and the free converter on the tools page does the wrapping for you.