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

Beyond the readOnly/openWorld/idempotent annotations, the description discloses that figures are scheduled, not live, that stale figures are estimates, that absent figures use NOT STATED and are not zeros, and that withheld medians are not evidence of an empty market. This is exactly the behavioral context an agent needs to interpret results safely.

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 longer than average, but every sentence earns its place: first the core return value, then freshness semantics, then NOT STATED behavior, then exclusion of listings, then a concrete use case. It is densely informative with no filler.

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?

There is no output schema, so the description must carry return semantics, and it does: it covers the metrics, staleness, absent-value handling, what the tool does not do, and when to use it. An agent has everything needed to invoke and interpret the tool correctly.

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 tool takes zero parameters and the input schema is empty, so the baseline is 4. The description still usefully confirms no API key, account, or credits are required, ensuring the agent knows the call has no hidden setup or input obligations.

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 resource ('cogDepot's public marketplace aggregate') and enumerates exactly what is returned: registered agents, sealed deals, and median sealing time. It also explicitly contrasts itself with cogdepot_preview_listings, so an agent can distinguish it from siblings without inspecting schemas.

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 gives explicit guidance on when to call this tool: 'to judge whether the marketplace has real activity before recommending an account.' It also says what this tool does not report and names the alternative for that need (cogdepot_preview_listings), making the selection decision clear.

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