pdf_extract

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

With no annotations, the description carries the full burden and does well: it discloses cost ($0.0055 USDC per call), p99 latency (1500ms), the ~10 MB decoded size ceiling, and the exact return shape. Auth requirements and failure/error behavior remain unstated, so it falls short of a 5.

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?

Purpose is front-loaded and the sentences are dense with payoffs (return shape, cost, latency). The Buffer.from(...).toString('base64') snippet is arguably redundant given the schema's own base64 description, a minor bit of bloat against an otherwise tight entry.

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?

There is no output schema, so the description correctly summarizes the return fields (text, pages, page_count, metadata) along with cost, latency, and size limits – enough for an agent to invoke and anticipate the response. Error cases and truncation behavior for the default max_pages=50 are not covered.

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 coverage is 100%, so the baseline is 3. The description restates both parameters (pdf_base64 and its size limit) and adds a concrete encoding recipe, but that content largely duplicates what the schema already documents rather than adding new semantic meaning.

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?

States a specific verb and resource ('Extract all text from a PDF') and names the exact input mechanism (pdf_base64), making it distinguishable from siblings like ocr, doc_parse, or webpage_reader without opening the schema.

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?

Gives intended use cases ('Ideal for RAG pipelines, document QA, or LLM ingestion'), which implies when to reach for it, but never contrasts with the many adjacent siblings (ocr, doc_parse, page_extract). No when-not guidance and no explicit alternative routing.

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