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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior. The description adds meaningful context by describing what the report contains, noting that the long-form report is included only 'when V³ has authored one', and directing further details to the canonical URL. This goes beyond annotations without contradicting them.

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 appropriately sized, with the main purpose front-loaded and a concise list of return components. It avoids unnecessary filler and directly communicates the essential information. Minor improvement could be splitting the return list for scannability, but it is already clear and efficient.

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 read tool with a rich output schema, the description covers the return content, the id source, and points to where additional data lives. It does not mention error scenarios or URL format, but these are not critical for a read-only fetch tool. The context is complete enough for correct selection and invocation.

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?

The schema only defines 'id' as a required string with no description, so the description carries the burden. It explains that the id is the V³ event id returned by 'search', which is exactly the semantic detail an agent needs. For a single parameter with 0% schema coverage, this is sufficient.

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 verb (Fetch) and resource ('full text of a single V³ event by id'), and clearly identifies the id source as 'from search'. It details the return payload, which helps an agent understand what the tool produces. However, it does not explicitly distinguish itself from sibling v3_get_event or other v3_* tools, though the reference to search narrows the context.

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?

The description explicitly says to use an id returned by 'search', which provides clear guidance on the prerequisite call. It implies this tool is for retrieving a specific event's full report, but it does not enumerate when to use alternatives like v3_get_event or v3_search_events. The context is clear and actionable, but lacks explicit exclusions.

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