get_incarnations

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

No annotations are present, so the description carries the burden. It discloses the return shape ('A dict with an `incarnations` list') and the fields included, but does not mention ordering, completeness, or error behavior. For a simple list tool, this is adequate but not exhaustive.

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 paragraphs with no redundant information. Each section (overview, usage, returns) serves a distinct purpose and 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?

Given 0 params and no output schema, the description provides enough detail about the output structure and the tool's role relative to a sibling tool. It could include an example but is not necessary for a straightforward list tool; the description is complete for its complexity.

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?

There are zero parameters, so the schema and description have nothing to clarify. Baseline of 4 applies as there is no parameter information to miss.

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 opens with a clear verb 'List' and specifies the resource 'King Crimson's line-up eras (incarnations)', followed by an enumeration of returned fields. It also distinguishes itself from the sibling `song_performance_history` by positioning itself as the reference for incarnation IDs/names.

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?

It explicitly states 'Use this to look up who played in a given era' and references the sibling `song_performance_history` to note that its per-era counts are keyed by the same IDs/names, making this tool the lookup reference. This gives clear when-to-use guidance and points to an alternative for related data.

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