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

Goes well past the readOnly/non-destructive annotations by disclosing what is returned (ordered parts, per-part words or name, millisecond length, per-part include/exclude styles), a model-dependent format difference (chunks vs. sections), and that the call makes no audio and costs no tokens. That is exactly the context an agent needs to decide whether to plan before generating.

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?

Front-loaded with the core action and the free/no-audio caveat arrives early; every sentence carries useful information. Minor redundancy between 'before anything is charged' and the closing 'does not make audio and does not cost tokens' keeps it from a 5.

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?

There is no output schema, yet the description fully specifies the return shape (ordered parts, names/words, lengths in ms, styles to keep in and out) and how to consume it downstream via generate_music. Nothing an agent needs to call or interpret this tool is missing.

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 `prompt` and `seconds` are already fully documented with an example and range/ default, which sets the baseline at 3. The description adds only indirect meaning ('describe the track you want', plan 'lays its sections out' to fit the length) rather than any new syntax or format guidance beyond the schema.

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 ('Draft the plan for a music track') plus a precise scope constraint ('before any of it is made, and before anything is charged'). It also distinguishes itself from the obvious sibling by naming generate_music and explaining the handoff relationship.

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?

Gives an explicit when-to-use rule ('longer or structured pieces (intro, verse, chorus, drop, outro) where a single sentence will not get the shape right') and names the alternative workflow step (pass the plan to generate_music to hear it). It also states the cost condition, which is a genuine selection factor versus generate_music.

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