download_book

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Discloses mirror fallback order and return fields (local file path, size_bytes, extension). No annotations exist, so description carries burden. Lacks details on potential issues like timeouts, size limits, or authentication requirements.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with purpose, no superfluous text. Every sentence adds value.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

No output schema, but description lists return fields. Covers basic usage but misses timeout, error handling, file size warnings for a download tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema has 100% coverage. Description adds context: md5 is 'from search results', title is 'used for filename', enhancing meaning beyond schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Specifies verb 'Download' and resource 'book from LibGen by MD5 hash'. Clearly distinguishes from siblings: get_formats gets formats, search_books searches. Includes output fields.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Implies usage after obtaining MD5 hash from search, but no explicit when-to-use or when-not-to-use. Mentions automatic mirror fallback but no alternatives or exclusions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.