recent_scrobbles

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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so the description's 'Read-only' adds nothing beyond the structured data. It provides no additional behavioral context such as time-range boundaries, pagination behavior, or rate-limit considerations, and the local-default note already appears in the schema.

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?

The description is three short sentences, front-loading the primary purpose and staying scannable. The redundant read-only note is harmless, and no filler or vague phrasing is present.

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 read-only list tool with all parameters documented in the schema and safety covered by annotations, the description covers the essentials. It omits return-format details, but no output schema exists and 'scrobbles' plus the limit parameter make the result shape inferable, so only a small gap remains.

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%, with clear descriptions for to, from, limit, and username. The description's 'Pass a username unless the server has a local default' mirrors the schema's username description, adding no new meaning, 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 'Get a Last.fm user’s most recent scrobbles' states a specific verb and resource, immediately distinguishing it from siblings like top_items, artist_history, and rediscovery_candidates. The purpose is unambiguous and the resource scope is clear.

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?

No explicit guidance is provided on when to choose this tool over its siblings. The only usage hint, 'Pass a username unless the server has a local default,' addresses parameter handling rather than tool selection. Usage is implied by the purpose statement but not elaborated.

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