market_stats

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and a closed-world scope, so the safety profile is covered. The description adds useful context that the counts are derived from existing reports and that they cover both relevant and new postings. It says nothing about rate limits, cost, or data freshness/lag beyond the report-parsing note.

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?

One sentence that front-loads the output shape and then characterizes the tool's role. It is efficiently sized with no filler, though "a quick pulse of the niche market" is slightly promotional rather than informative.

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 single-optional-param, read-only aggregation tool, this is close to sufficient; the output schema exists so return values need not be re-explained. What's missing is any indication of how the result is scoped (e.g. which market/niche is being measured), which matters given the description's ambiguity about scope.

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 0%, but the single "days" parameter is semantically explained by "over the last N days", which tells the agent the window is a trailing range rather than a calendar range. The 30-day default is only visible in the schema, which is acceptable.

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 names a specific output (per-day counts of relevant and new postings) and the source (parsed from the reports), so an agent knows exactly what this tool produces. It doesn't reference any sibling (latest_report, search_jobs, is_seen), so differentiation from nearby tools is left to inference.

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?

"A quick pulse of the niche market" implies a summary/overview use case, which gives some sense of when to reach for it. However, there is no explicit when-to-use vs. when-not, and no routing to alternatives like latest_report or search_jobs for detailed data.

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