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

With no annotations, the description carries the burden, but the tool is a zero-parameter read-only listing, so risk is inherently low and the verb 'List' makes the read nature clear. The 'Free.' prefix usefully discloses cost, but there is no mention of response size, pagination, or rate behavior for what could be a large index of APIs.

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?

Two short sentences with no waste, and the cost note is front-loaded before the action. Everything an agent needs is in the first clause.

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, annotation-free listing tool with no output schema, the description adequately covers what it returns (APIs, routes, query parameters). It stops short of telling the agent how the result should be used to pick among the sibling data tools, which is the one remaining gap.

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 no parameters, so the baseline is 4. The description's note that listed APIs include routes and query parameters describes the payload rather than inputs, which is helpful context but not required for invocation.

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 ('List all Lilambd data APIs') and adds what the listing contains (routes and query parameters), which is more than a restatement of the name. It does not explicitly differentiate itself from the many data-category siblings (airports, colors, markets, etc.), though the plural 'APIs' implies this is the discovery/index tool.

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?

Usage is only implied: an agent can infer this is the entry point for discovering what Lilambd offers before calling a specific data tool, but the description never says so or names any sibling as an alternative. No exclusions or preconditions are given.

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