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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), and the description goes well beyond them by disclosing hard limits (12 pages / 24000 chars, max_chars up to 60000), the pagination behavior (pages_returned, next_pages), and the fallback links returned. That is exactly the operational context an agent needs to page correctly.

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?

Three dense sentences with the return format front-loaded, then limits, then usage guidance. Every clause carries information (markers, caps, pagination fields, full-file alternative) with no filler.

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?

With no output schema, the description compensates by naming the fields the result returns (pages_returned, next_pages, markdown/PDF links) and the citation markers. Combined with annotations covering safety, an agent has everything needed to invoke and page through the 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 coverage is 83% (>80%), so the schema documents most parameters, including the page-range pattern and max_chars bounds. The description reinforces doc_id/page-range/max_chars but adds no syntax or format detail beyond the schema, so the baseline 3 applies.

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: 'Markdown text of a parsed filing by doc_id and page range.' It is clear what the tool returns and how it is scoped, but it never names the obvious siblings (get_document_summary, list_company_documents) to disambiguate, so an agent must infer the boundary from the schema's doc_id reference.

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 real context for use: 'Annual reports run 100-400 pages: read the sections you need, or download links.markdown_url to search the whole file.' This names an alternative (whole-file download) and the condition that selects it, though it stops short of stating explicit when-not-to-use cases.

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