openf1_sessions

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

Annotations already declare readOnlyHint and idempotentHint, so the safety profile is covered. The description adds the return format (top-level array with specific fields) and explicitly states no auth is needed, which is useful beyond annotations. It does not mention rate limits or pagination, but for a read-only list endpoint this is acceptable.

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 compact and front-loaded: a one-line purpose, then return format, then auth note. No filler; every sentence conveys actionable information.

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 100% schema coverage and annotations, the description is sufficient: it lists the return fields, notes no auth, and explains the filtering purpose. It could mention behavior with no filters (e.g., returns all sessions) but that is minor given the openWorldHint and schema.

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 100%, so the schema already documents all seven parameters. The description adds a slight prioritization by calling out 'filter by year, country or session_name', but this doesn't add substantial new meaning. Baseline 3 is appropriate.

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?

Description uses a specific verb+resource: lists F1 sessions (Practice/Qualifying/Sprint/Race) and identifies itself as the 'fixtures feed'. It clearly distinguishes from sibling tools like openf1_meetings and openf1_session_result by explaining its role in the workflow (find a session_key).

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?

Provides clear context: it's the fixtures feed for finding session_keys by year, country, or session_name. It implies when to use (need schedule) vs. when to use other tools (need results), but doesn't explicitly name alternative tools or exclusion criteria.

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