estimate_music_cost

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

Annotations already declare readOnlyHint=false, destructiveHint=false, openWorldHint=true. The description adds real value beyond them: it discloses that the call persists a saved quote ('Save a 10-minute music quote'), what the response contains ('alternative entitlement costs for internal budgets'), and a display constraint on the returned data. This is meaningful behavioral context, not a restatement.

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 dense sentences, each carrying a distinct instruction (save semantics, model defaulting, output filtering), with the core action front-loaded. No filler, though 'internal budgets' and 'alternative-branch wording' are terse enough to require inference.

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 output schema, the description does explain the return shape ('display.estimated_costs', universal vs specialized credits) and that it does not generate. However, it leaves most of the six parameters undocumented, which is a gap for a tool with such low schema coverage.

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 only 17% – just mv is documented. The description addresses mv ('pass default_mv from list_music_models') but leaves style, title, action, lyrics, and instrumental entirely unexplained in both schema and description. With low coverage the description should compensate, and it largely does not.

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: 'Save a 10-minute music quote bound to exact input.' The closing 'Does not generate' disambiguates it from the generate_music sibling, though no sibling is named explicitly and the 'estimate vs save' framing is slightly muddled by the tool name.

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 concrete routing guidance: 'Unless the user specified a model, pass default_mv from list_music_models' and 'Does not generate' implies when to use generate_music instead. It also constrains output display (only universal credits). No explicit when-not conditions beyond the generation note.

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