read_document

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

With no annotations, the description carries the full burden and does so well: it discloses per-call limits (10 pages / 40,000 characters), the next_page continuation mechanism, the citation payload returned per page, and the untrusted-text marker convention with an explicit prompt-injection warning. This is rich behavioral context beyond what the schema offers.

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?

Four tight sentences, front-loaded with the core action and limits, then citation and safety guidance. Every sentence earns its place 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?

An output schema exists so return values needn't be re-explained, and the description still covers limits, continuation, citation format, and the untrusted-data handling. Nothing needed to call the tool correctly is missing.

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 doc_id, page_start and page_end are already documented in the schema. The description adds the page/character ceiling that governs page_end choices but 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 (Read) and resource (text of a document's pages) with clear scope, and the pagination/citation details make it easy to distinguish from siblings like grep_documents (search) and get_document_outline (structure only).

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 implied usage via the next_page continuation hint and 'cite pages you rely on', but never explicitly says when to prefer this over grep_documents or get_document_outline for locating content. No exclusions or alternatives are named.

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