Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add instructions/hald/things-mcp/claude-mdgit clone --depth 1 https://github.com/hald/things-mcpWrote 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/instructions/hald/things-mcp/claude-md)<a href="https://agentmods.dev/instructions/hald/things-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/hald/things-mcp/claude-md.svg" alt="Measured on agentmods" 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 | $0.01043 | $0.01043 |
| Opus 5 | $0.00522 | $0.00522 |
| Sonnet 5 | $0.00209 | $0.00209 |
| Haiku 4.5 | $0.00104 | $0.00104 |
Grade A, and why
things-mcp CLAUDE.md scanned grade A with 0 findings 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 5d ago.
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.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 95 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
Commands
Development Setup
# Install dependencies (uses uv package manager)
uv sync
# Run the MCP server (stdio transport, default)
uv run things-mcp
# Run with HTTP transport
THINGS_MCP_TRANSPORT=http uv run things-mcp
Testing
The project includes a comprehensive unit test suite covering URL scheme construction and data formatting functions.
# Install test dependencies
uv sync --extra test
# Run all tests
uv run pytest
# Run tests with verbose output
uv run pytest -v
# Run specific test file
uv run pytest tests/test_url_scheme.py
# Run tests matching a pattern
uv run pytest -k "test_format"
Test coverage includes:
- All URL construction functions (add, update, show, search)
- Authentication token handling
- Data formatting for todos, projects, areas, and tags
- Error handling and edge cases
- Mock external dependencies (Things.py, shell commands)
Architecture Overview
This is a Model Context Protocol (MCP) server that bridges Claude Desktop with the Things 3 task management app on macOS. The architecture consists of:
- src/things_mcp/server.py - Main MCP server implementation using FastMCP (3.x)
- Defines all MCP tools for interacting with Things (26 tools)
- List views (inbox, today, upcoming, etc.)
- CRUD operations for todos/projects/areas (Areas have create/read/update — no delete by design; see below)
- Search and tag operations
- Things URL scheme integration
- Implements Someday project filtering to match Things UI behavior
- Pagination + structured responses: the 16 list/search read tools accept optional
limit/offsetand return a FastMCPToolResultcarrying both a human-readable text channel and astructured_contentenvelope{items, count, total, offset, limit}. Two helpers drive this:_paginate_format(text) and_paginate_result(wraps text + JSON-safe structured data);_error_resultwraps early-return/validation errors.get_tag_usageintentionally stays a plain string.
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.
- 5d ago First seen · 95 lines · 1,043 tokens per session scan A 4cc10ab30ea3
things-mcp CLAUDE.md is an instructions file published in the GitHub repository hald/things-mcp (578 stars, last pushed 3mo ago), licensed MIT. It adds 1,043 tokens to every session, about $0.0052 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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