artist_decade_span

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

With no annotations present, the description carries the full behavioral burden and does disclose a meaningful trait: quota cost (🟡) and the underlying 'one paginated /artists/{id}/albums walk'. This helps the agent weigh cost before calling. It stops short of confirming read-only posture or describing response details, but the quota/operation disclosure is genuine added value beyond structured fields.

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 with zero filler: the first front-loads the core deliverable (histogram + dominant decade) and the second adds the quota constraint. Every sentence 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 low-complexity analysis tool with all three parameters documented in the schema and no output schema, the description covers the core computation, the headline insight, and the quota profile. Minor gaps (explicit read-only confirmation, output format across response_format values) are largely mitigated by the schema's enum documentation.

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 100%, so the baseline is 3; the description adds little parameter-level detail beyond implying the /artists/{id}/albums walk behind artist_id. It correctly avoids repeating schema docs, and the schema already documents include_groups defaults and response_format enum semantics.

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 states the tool produces a 'Histogram of an artist's releases per decade' with 'the dominant decade called out', which is a specific output over a clear resource. It is reasonably distinctive from siblings like artist_discography_timeline or era_distribution_report, though it doesn't explicitly contrast itself with those alternatives.

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?

The phrase 'instantly see which era carries the catalog' implies the usage context — quick era-level assessment of an artist's catalog — but there is no explicit when-to-use guidance or named alternatives. The agent must infer when this is preferred over the many sibling artist-analysis and era-report tools in the large sibling list.

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