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

No annotations are provided, so the description carries the full behavioral burden. It usefully discloses that the return payload is user-generated Instagram content and should be treated as untrusted (a prompt-injection-relevant trait not derivable from the schema), but says nothing about permissions, rate limits, error behavior, or pagination.

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 short sentences, purpose front-loaded and the trust caveat placed second. No wasted words and nothing buried.

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 read tool with a fully documented schema and no output schema, the description covers purpose plus the important untrusted-content caveat. A brief note on what the track object contains or on missing/invalid IDs would make it complete.

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?

With a single parameter and 100% schema description coverage ('Track ID (pk)'), the schema already documents the input fully. The description's 'by ID' adds no syntax, format, or constraint detail beyond what the schema states, so the baseline 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 gives a specific verb and resource ('Get music track by ID') with an explicit lookup key, which is enough to distinguish it from search_tracks and get_top_tracks in practice. It does not, however, name or contrast itself against those siblings, so it stops short of a 5.

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?

There is no stated when-to-use, when-not-to-use, or alternative routing guidance. The second sentence is a trust/safety warning, not usage direction, so an agent must infer that this tool is for single-track lookup when an ID is already known.

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