pdf_outline

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

With no annotations, the description carries the burden of behavioral disclosure. It conveys that this is a read operation and describes the output as JSON with target pages, which is useful. However, it does not mention edge-case behavior such as missing bookmarks, invalid files, or file-access expectations, leaving some ambiguity for a tool with zero annotation support.

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?

The description is one tight sentence that front-loads the verb and object, then gives output format, use cases, and cost. Every element earns its place; there is 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?

For a low-complexity read tool with a single parameter and no output schema, the description gives enough to select and call it: what it reads, what it returns, and why it is useful. The main gap is lack of error/edge-case details and explicit note that no outline may produce an empty result, but these are minor for such a simple 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?

The schema only declares `file` as a required string with no description, and schema coverage is 0%. The description partially compensates by indicating that `file` is the PDF whose outline is read, but it does not specify how the file should be referenced (path, URL, uploaded ID) or any formatting expectations.

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?

The description names a specific verb ('Read') and resource ('a PDF's bookmark/chapter outline') and specifies the output form ('JSON with target pages'), so the tool's job is unambiguous. It does not explicitly name sibling tools to differentiate against, but the outline-specific wording distinguishes it from pdf_info and pdf_to_markdown without needing to open their schemas.

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?

The description explicitly states the intended use: obtaining chapter boundaries 'for navigation or chunking', which tells an agent when to choose this tool. It does not provide exclusion criteria or contrast with alternatives, so it stops short of a 5.

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