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

Annotations already cover readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, so the safety profile is known. The description adds meaningful context beyond the annotations by clarifying that this is captured market data rather than exhaustive historical coverage, and by noting the generation timestamp. No contradiction with annotations exists.

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 two sentences with no filler. The main action and contents are front-loaded, and the caveat about baseline-only usage is placed at the end without redundant elaboration.

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-parameter, read-only, idempotent tool with no output schema, the description is complete: it states what is returned, the data scope, and the appropriate use case. An agent has everything needed to invoke the tool correctly and interpret its output at a high level.

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 has zero parameters and the schema description coverage is 100%, so there is no parameter documentation burden. The baseline for a zero-parameter tool is 4, and the description appropriately spends no space on parameters.

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 opens with a specific verb and resource: 'Return the corpus-level figures the site publishes,' then enumerates exactly what is included: launches captured per chain, resolved counts, shares that rugged/died/survived/graduated, and the generation timestamp. This level of specificity makes it clearly distinguishable from sibling tools that focus on per-creator or per-scan operations.

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 provides explicit usage guidance: 'use it for baselines, not for totals of all activity' and warns that the data is 'not exhaustive coverage from a start date.' This gives the agent a clear positive and negative condition for when to invoke this tool rather than similar data tools.

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