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

Annotations already declare readOnlyHint=false, destructiveHint=false, openWorldHint=true, so the description's 'write (not read-only), additive, never destructive' mainly repeats structured data. However, it adds genuinely useful context beyond annotations: the created item is 'pending', the write goes through the REST API, and it details API-key acquisition and authorization requirements. This is solid but not exhaustive (e.g., no mention of rate limits or idempotency behavior).

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 front-loaded with purpose and usage, then behavior, auth, and required fields. It is mostly efficient, but the 'write (not read-only) that is additive, never destructive' clause largely duplicates the annotations and could be trimmed.

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?

Given the tool is a write with a nested event object, sibling alternatives, API authentication, and an existing output schema, the description covers what an agent needs: purpose, when to use it, auth procedure, pending state, and required/conditional event fields. Nothing critical for correct invocation appears missing.

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 baseline is 3. The description adds a conditional requirement beyond the schema: 'city and country are required for non-online events.' That conditional semantics is meaningful for correct invocation, though the schema already documents starts_at as required.

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 gives a specific verb+resource ('Submit an upcoming event... to the events product'), lists concrete examples, and explicitly contrasts itself with report_incident. An agent can distinguish this from siblings like find_events and query_security_feed without opening any schema.

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 states when to use this tool ('to contribute event listings') and names the alternative for non-event signals ('use report_incident for non-event signals'). The routing condition is explicit rather than implied.

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