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

Beyond the readOnlyHint annotation, the description reveals meaningful behavior: stations with end dates within the last 24 hours are flagged active, earlier dates are discontinued, and most monitoring ended October 2024 due to the Internet Archive feed. This gives the agent valuable expectations about data freshness and discontinuation that are not inferable from the schema or annotations.

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 front-loaded with the core purpose in the first sentence, then adds the active-flag definition, usage guidance, and historical context in subsequent sentences. Every sentence earns its place and there is no redundant 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?

With zero parameters and an output schema available, the description needs only to explain what the list contains, how to interpret status, and when to call it. It covers all of that, including the important real-world limitation about October 2024, making the tool fully understandable without additional context.

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, so the baseline is 4 by rubric. The description correctly focuses on the output rather than parameters, and since there are no inputs to document, no additional parameter semantics are needed.

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: 'List all television stations available for TV search,' and details the exact fields returned (market, network, monitoring start/end date). It clearly distinguishes itself from the sibling TV tools by establishing that this is a reference-list endpoint for station discovery, not a search or analysis 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?

The description explicitly states when to use the tool: 'Use before querying to verify a station was active during the target time period, or to discover valid station IDs for the stations parameter in other TV tools.' It provides clear context but does not name specific alternatives or state when not to use it, stopping just short of full exclusion guidance.

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