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

Annotations already cover readOnly=false, openWorld=true, idempotent=false, so safety profile is known. The description adds useful behavior ('images one page each, in order') but says nothing about processing latency, job polling (get_job exists), or failure modes for a non-idempotent conversion.

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 sentences, zero filler, with the capability statement front-loaded and the disambiguation as a trailing clause. 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?

An output schema exists, so return values needn't be described, and the annotations carry the safety profile. The remaining gap is that a six-parameter, zero-required-input converter doesn't hint at which input field to pick or that conversion may be asynchronous.

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 adds only the meaning of 'url' as a public web page and the ordering semantics for images; it doesn't clarify the three overlapping file-input modes (files, file_ids, file_urls) or library_file_id.

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+resource ('Make a PDF') and enumerates supported input types (Word/Excel/PowerPoint, images, EPUB, web page). It also names the sibling it differs from (create_pdf), so the agent can distinguish it without opening 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?

Explicitly routes self-authored content to create_pdf, which is the main ambiguity for this tool. It doesn't mention the inverse tool convert_from_pdf or when a library/URL file should be preferred, but the usage context is clear.

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