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

The annotations already declare readOnlyHint and idempotentHint, so the tool is safe and deterministic. The description adds no further behavioral details beyond its purpose, but that's acceptable given the annotations cover the safety profile. No contradictions.

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?

A single, front-loaded sentence that states exactly what the tool reports with no extraneous information. It's concise and well-structured.

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 simple informational tool with no parameters and no output schema, the description sufficiently indicates what the agent will receive: data vintage and refresh frequency. It doesn't specify units or format, but for this purpose, it's complete enough.

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 no parameters, so the schema is empty. Per the baseline for zero parameters, the description need not explain parameters. The description doesn't add any parameter-related info, which is appropriate.

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 states the specific resource (loaded price data) and the two attributes (vintage and refresh frequency) it reports. This clearly distinguishes it from siblings like compare_plans, list_assets, and run_dca. However, it lacks an explicit verb like 'returns' or 'reports', so it's not a full sentence, but the intent is clear.

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 implies the tool is for checking data freshness, but it does not explicitly state when to use it or mention alternatives. For a tool with zero parameters, the usage is straightforward, but without explicit guidance, it relies on inference.

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