Get indexed corpus row counts

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false, so the safety profile is fully covered elsewhere; 'read-only health check' and 'does not export or transfer data' largely restate it. The description does add value by naming the table families whose counts are returned, but omits cost, latency, and whether counts are exact or approximate.

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?

Three short sentences, front-loaded with the core purpose, then usage framing, then a scoping exclusion. No redundancy of substance, though the final exclusion sentence is thin given annotations already mark the tool read-only.

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 zero-required-parameter, single-enum tool with a full-coverage schema, the description supplies enough: what is counted, that it is a health check, and that no data moves. The absence of an output schema is partially mitigated by enumerating the row-count categories, though exact response shape remains unspecified.

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?

There is a single optional 'format' parameter with 100% schema description coverage and an explicit enum, so the schema fully carries parameter meaning. The description says nothing about format selection or what markdown vs. json output looks like, leaving it at the baseline for high-coverage schemas.

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?

Specific verb+resource: 'Get row counts for indexed developer-research corpus tables,' and it enumerates the entity types counted (sessions, documents, summaries, cross-reference records). It does not, however, differentiate itself from the nearby sibling wwdc_ingest_status, which an agent could plausibly confuse with a corpus health/count check.

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 frames the tool as a 'read-only health check,' which implies when to reach for it, and the negative clause 'does not export or transfer data' rules out one misuse. But it names no alternative and gives no condition distinguishing it from wwdc_ingest_status or from actual search/list tools when an agent wants to know what content exists.

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