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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds real value beyond them: results are grouped by state, distance is reported in km, and venue ids feed search_sessions. It omits pagination and default-listing behavior, which keeps it from a 5.

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?

Three sentences, all front-loaded: purpose first, then the two parameter modes, then the id hand-off. No filler and every clause carries information an agent will use.

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 an output schema present, the description need not explain return values, and it still usefully mentions grouping and distance units. The main remaining gap is disambiguation from the similarly shaped search_nearby_sessions sibling.

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 all three parameters are already documented, including 'state' being ignored when 'near' is given. The description reinforces the near/state interplay and the postcode-or-suburb format but adds little syntax or semantics the schema lacks. 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?

States a specific verb+resource: 'List training venues with address, grouped by state,' and ties its output to a sibling by noting the venue id is 'the location for search_sessions.' It does not, however, distinguish itself from search_nearby_sessions, which the 'near' mode appears to overlap with.

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?

Gives clear mode-selection guidance: pass 'state' to narrow to one state, or 'near' to get the closest venues with distance. It stops short of explaining when to prefer this tool over search_nearby_sessions/search_sessions, leaving the closest alternative unresolved.

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