engineering-coworker (crates/engineering-coworker)
A Rust MCP server (rmcp, stdio) that executes cargo/wrangler/git/D1 operations on the developer's real Mac on Claude's behalf — Claude is never handed the raw credential, mirroring claude-tag's own Agent Proxy: "Agent Proxy attaches a credential... the model and the sandbox itself are not given the key."
The Mac's own git/cargo/wrangler auth (SSH keys, cargo registry token, wrangler OAuth session) — held by the binary process, never passed through to the calling model
cargo_check, cargo_test, wrangler_deploy, d1_query, git_status, git_commit_push — exactly the six tools this binary exposes, no more
The operator whose Mac the binary runs on — attribution flows through, same as any macos__* surface action
CLAUDE.md, "engineering-coworker MCP server (crates/engineering-coworker)"; agent-identity.md, "Agent Proxy" (Anthropic's own Agent Proxy pattern this binary parallels in spirit)
created 2026-07-01 18:49:26