Borrowing it
Nothing to install: this file belongs to democratize-technology/chronos-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/democratize-technology/chronos-mcp/main/CLAUDE.mdgit clone --depth 1 https://github.com/democratize-technology/chronos-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/democratize-technology/chronos-mcp/claude-md)<a href="https://agentmods.dev/instructions/democratize-technology/chronos-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/democratize-technology/chronos-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 5.1 | $0.01075 | $0.01075 |
| Opus 5 | $0.00537 | $0.00537 |
| Sonnet 5 | $0.00215 | $0.00215 |
| Haiku 4.5 | $0.00108 | $0.00108 |
Grade A, and why
chronos-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 8d 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 — 142 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.
Core Commands
Development
# Install for development with all dependencies
make dev-install
# Run the MCP server
./run_chronos.sh
# or
python -m chronos_mcp
# Format code (required before committing)
make format
# Run linting checks
make lint
# Run all tests
make test
# Run specific test categories
make test-unit # Unit tests only
make test-integration # Integration tests only
# Run tests with coverage
make coverage
# Run a single test file
pytest tests/unit/test_events.py -v
# Run a specific test
pytest tests/unit/test_events.py::test_create_event -v
# Clean build artifacts
make clean
Linting and Formatting
# Format with black and isort
black chronos_mcp tests
isort chronos_mcp tests
# Check formatting without modifying
black --check chronos_mcp tests
isort --check-only chronos_mcp tests
# Type checking
mypy chronos_mcp
Architecture Overview
Chronos MCP is a Model Context Protocol server for CalDAV calendar management built with FastMCP 2.0. The codebase follows a layered architecture:
Key Components
-
MCP Interface Layer (
server.py)- Defines MCP tools using FastMCP decorators
- Handles input validation and error sanitization
- Maps tool calls to business logic managers
-
Tool Interface Layer (
tools/)tools/base.py: Base tool manager class with connection cachingtools/accounts.py: Account management toolstools/calendars.py: Calendar CRUD toolstools/events.py: Event lifecycle toolstools/tasks.py: VTODO task toolstools/journals.py: VJOURNAL journal toolstools/bulk.py: Bulk operation tools- Delegation pattern: server.py delegates to tools/, tools/ delegate to business logic managers
-
Business Logic Layer
accounts.py: Multi-account management with connection cachingcalendars.py: Calendar CRUD operationsevents.py: Event lifecycle including recurring events (RRULE)tasks.py: VTODO task managementjournals.py: VJOURNAL journal entry managementbulk.py: Parallel bulk operations with rollback supportsearch.py: Advanced search with relevance ranking
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.
- 8d ago First seen · 142 lines · 1,075 tokens per session scan A cea723fcdbc7
chronos-mcp CLAUDE.md is an instructions file published in the GitHub repository democratize-technology/chronos-mcp (29 stars, last pushed 1mo ago), licensed MIT. It adds 1,075 tokens to every session, about $0.0054 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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