Read media file

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

Annotations already declare readOnly/idempotent/non-destructive/openWorld=false, so the safety profile is covered. The description adds genuine behavioral detail beyond them: a PDF yields one page (default 1) rendered as JPEG plus the total page count. It does not describe what images/audio return, so it is not a full 5.

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, front-loaded with the capability, followed by return behavior and then alternatives. No filler, every clause 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 one-parameter read tool with full annotation coverage and no output schema, the description covers capability, PDF return behavior, and routing. The only gap is what is returned for image and audio inputs, which is left implicit.

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 0% for the single 'path' parameter, so the description must compensate and it does: it documents the '#N' path suffix convention for selecting a PDF page and the default of page 1. That is a real semantic addition the bare schema lacks.

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 set ('Read an image, audio or PDF file') and immediately names the two PDF-oriented siblings it is not (read_pdf_text, read_pdf_page). An agent can tell this apart from the other read tools without opening a schema.

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 the agent: PDF text goes to read_pdf_text, a single PDF page as an image goes to read_pdf_page, and this tool handles images/audio/whole-PDF-as-media. The when-not condition for the named alternatives is stated rather than implied.

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