detect_headings

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

No annotations are provided, so the description carries the behavioral disclosure burden. It discloses that results are heuristic 'candidates' derived from font sizes, which is useful. It does not describe output shape, limitations, or side effects, but for a read-like detection tool this is a reasonable level of transparency.

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 concise sentences with no filler. The first sentence gives the action and method, and the second gives the practical use case. Every sentence earns its place.

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 single-parameter tool with no output schema, the description is largely complete: it explains what the tool does, how it does it, and when to use it. The main gap is that it does not hint at what the returned heading candidates look like, but this is not essential for selecting and invoking the tool correctly.

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 description coverage is 100%, so the parameter is already well documented as an absolute PDF path. The description adds no new parameter-level detail beyond repeating the PDF context, so the baseline score of 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?

The description clearly states a specific verb ('Detect'), a specific resource ('heading candidates'), and the method ('analyzing font sizes'). It also distinguishes itself from TOC/bookmark-based tools by explicitly targeting PDFs without TOC/bookmarks, which separates it from siblings like get_toc.

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?

It gives clear when-to-use guidance: use it for PDFs without a TOC/bookmarks, before reading, to understand document structure. However, it does not explicitly name alternative tools or state when not to use it beyond the 'without TOC/bookmarks' condition.

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