We needed a public, machine-readable vault of the navigation rules of the road — COLREGS rule text — to back an MCP server for a boat agent. The obvious plan: hand Claude the USCG Navigation Rules and Regulations Handbook PDF and ask it to transcribe each rule into a clean markdown file. The text is a US Government work in the public domain. Free to copy, free to redistribute.
Claude read the whole PDF, started writing, and then the Anthropic API hard-blocked it:
API Error: 400 Output blocked by content filtering policy
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