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 credit cost (1 credit per minute), asynchronous behavior for long jobs, the get_job polling path, and 1-hour result link expiry. It omits auth/permission requirements and any failure/rate-limit behavior, so it stops short of a 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?

Three tight sentences with the capability front-loaded, then cost, then async/expiry mechanics. No filler, though the sentences are somewhat telegraphic rather than optimally organized.

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?

With no annotations and no output schema, the description must cover the operational contract, and it does: output format (PNG), cost, async flow, and link lifetime. Missing details are limited to authentication and the shape of the returned link, both minor for calling 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 only 40% (url and color documented, type/width/height bare). The description restates the waveform/spectrogram choice matching the enum but adds nothing about the sizing or color parameters, so it fails to compensate for the documentation gap.

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+output: renders an audio or video file's sound as a waveform or spectrogram PNG. No sibling tool (process_audio, analyze_media, extract_audio) does the same thing, so an agent can distinguish it immediately.

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?

Usage is implied by the capability statement and the async note (poll job_id with get_job) routes the agent onward for that case. However, there is no explicit when-to-use guidance versus alternatives like analyze_media or process_audio, and no statement of when this tool is the wrong choice.

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