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

Annotations already declare readOnlyHint=false, destructiveHint=false, openWorldHint=true and idempotentHint=false, so the submission/mutating nature is covered. The description usefully adds that one call is needed per distance and that `quote` is a verbatim copy from `source_url`, but it never says what happens after submission (moderation queue, duplicate rejection, review latency) — meaningful for a proposal tool.

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?

Four short sentences, front-loaded with the admission criterion and the prerequisite check before the parameter details. No filler; each sentence conveys a distinct constraint. Slightly telegraphic phrasing ('Send a US ultramarathon the index does not have yet') costs a bit of clarity.

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 7 parameters, no output schema, and 0% schema coverage, the description covers the two non-obvious fields and the multiplicity rule but leaves the remaining parameters and the post-submission outcome undocumented. Adequate to attempt a call, but not fully sufficient for an agent to predict what a successful submission yields.

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 0% across 7 parameters, so the description carries the burden. It explains `quote` well (verbatim from `source_url`, names the race) and clarifies `distance_category` through the one-race-per-distance rule, plus the US-only scope affecting city/state. But `name`, `city`, `state`, and `website_url` receive no semantic elaboration beyond their self-evident titles.

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 and resource ('Send a US ultramarathon the index does not have yet'), which pins both the action and the admission criterion of novelty. It implicitly separates itself from search_races (already-indexed races) and from propose_correction (fixes to existing entries), though the latter is never named explicitly.

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?

'Check with search_races first' is an explicit precondition naming the sibling to consult before calling. 'One call for each distance' gives concrete guidance on call granularity. It stops short of saying when-not to use it (e.g. use propose_correction for errors in an existing entry), so the exclusion side is inferred rather than stated.

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