MCP Script Rules

scripts/

DO

• Use CLI arguments for all parameters (argparse)
• Include USAGE docstring at top of file
• Use

  call_mcp_tool("server__tool", params)

  pattern
• Handle errors gracefully with informative messages
• Print results to stdout for Claude to process

DON'T

• Hardcode parameters in the script
• Edit scripts to change parameters (use CLI args instead)
• Import from servers/ directly (use runtime.mcp_client)

Tool Naming

serverName__toolName

• morph__warpgrep_codebase_search

• ast-grep__ast_grep

• perplexity__perplexity_ask

Testing

uv run python -m runtime.harness scripts/<script>.py --help