Engineering decisions, change impact, documentation audits, and CI evidence for coding assistants.
Mason helps your coding agent catch what a patch leaves behind: stale instructions, missed companion updates, and engineering decisions that need another look.
Works through MCP, with automatic documentation checks for Codex and Claude Code. No concept map required.
Install on macOS or Linux:
curl -fsSL https://github.com/adrianczuczka/mason/releases/latest/download/install.sh | sh
Windows PowerShell:
irm https://github.com/adrianczuczka/mason/releases/latest/download/install.ps1 | iex
No Node or npm required. Git is required. The installer configures PATH for Bash, Zsh, and Windows. Platform details · npm installation
Run this in your Git repository (open a new terminal if the installer asks):
mason setup --host codex
# For Claude Code, use --host claude.
Setup connects MCP, hooks, and project instructions. Review your host's trust settings, start a new session, and give your agent a normal task.
Check that Mason is being used:
mason status
Status distinguishes installed configuration from observed use. Setup and upgrades · Other MCP clients
mason audit --dir .
mason review --dir . --base origin/main
The audit checks claims in AGENTS.md and CLAUDE.md. The review checks committed changes against your chosen base. Both are read-only and need no model calls.
| As your project grows… | Mason helps by… |
|---|---|
| Instructions fall behind the code. | Flagging missing paths, incorrect workspace counts, and missing npm scripts. |
| A patch misses a related update. | Surfacing references, related tests, and files that historically change together. |
| Old decisions lose their context. | Retrieving recorded rationale and review status, and flagging changes to the code they apply to. |
| A repair gets interrupted. | Retaining the original findings and verifying them through the final documentation commit. |
After resolving an incident or settling a constraint, ask your agent to record the reason with Mason. Later tasks can retrieve it. Proposals and accepted decisions stay distinct.
Mason complements tests, linters, and code review. Findings are evidence to inspect; unavailable checks stay explicit.
Earlier read-only decision-retrieval evaluations scored 9.0/10 with Mason vs 7.0/10 without. The initial ten-task patch comparison tied at 10/10 for both. Improved patch outcomes remain to be demonstrated. Results, methodology, and limitations
Source-derived launch command. Check the maintainer’s required arguments and credentials before running:
npx -y mason-contextMerge this template into ~/Library/Application Support/Claude/claude_desktop_config.json. Keep existing servers. Add any arguments, credentials, and permissions required by the maintainer; this template has not been install-tested.
{
"mcpServers": {
"com-adrianczuczka-mason": {
"command": "npx",
"args": [
"-y",
"mason-context"
]
}
}
}Restart Claude Desktop completely for changes to take effect. Confirm the server appears connected in the client’s tool list, then try a read-only example from its documentation.
Claude Desktop setup referencemason-contextnpmcom.adrianczuczka/mason works with any MCP-compatible client. Copy the config snippet from the Configuration section above and add it to the file shown for your client, then restart the application.
~/Library/Application Support/Claude/claude_desktop_config.jsonRestart Claude Desktop completely for changes to take effect.~/.cursor/mcp.jsonRestart Cursor for changes to take effect..vscode/mcp.jsonReload VS Code window for changes to take effect.~/.codeium/windsurf/mcp_config.jsonRestart Windsurf for changes to take effect..mcp.jsonSave at the project root, then start Claude Code in that project and review the MCP server approval prompt. Keep real credentials out of shared files.