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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=true. The description adds only the HTTP endpoint and token format, neither of which provides meaningful behavioral context beyond what the structured metadata and schema already convey.

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 two short sentences with zero wasted words, and the core operation and identifier are front-loaded.

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 simple one-parameter retrieval tool with full schema coverage and rich annotations, the description is minimally adequate. It does not describe the response shape or any error behavior, but the low complexity limits the practical gap.

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 single event_token parameter is already fully documented in the schema. The description mentions the token format, but adds no syntax or semantic detail beyond the schema, making the baseline 3 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?

The description states a specific retrieval action ('One event') and identifier ('by token (evt_...)'), and the endpoint 'GET /events/{token}' makes the resource explicit. It implicitly distinguishes itself from list_events by specifying a single event, though it does not name the sibling alternative.

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?

Usage is implied by 'by token': use this when you have an event token. However, there is no explicit when-to-use guidance, no exclusions, and no direct comparison to the sibling list_events tool.

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