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

Annotations already declare the safety profile: readOnly, idempotent, non-destructive, closed-world. The description adds useful context by disclosing that this returns public details and related Festival Times articles. It does not describe error behavior for invalid or missing festivals, but the annotations reduce the burden.

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 compact sentences with no filler. The scope is front-loaded and the parameter guidance follows immediately.

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 one required parameter, no output schema, and annotations covering safety, the description is nearly complete: it lists the returned fields and explains how to obtain the identifier. It does not mention not-found behavior or whether related articles are paginated, which keeps it below a 5.

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 workflow meaning by saying the parameter should be the slug or URL returned by search_festivals, or the festival id, which helps the agent source the identifier correctly.

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 a specific resource and scope: full public details for one festival, then enumerates the returned fields. It distinguishes itself from search_festivals by referencing the slug/URL that search returns and by focusing on a single festival.

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 tells the agent to use a slug or URL returned by search_festivals, or a festival id, which establishes when this tool should be called. It does not state exclusions or contrast with other sibling tools, so it falls short of a full when/when-not guideline.

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