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

Annotations already declare it read-only and non-destructive. The description adds value by disclosing that calls are preserved even if deleted, a $0.02 USDC cost, and a truncation flag for total count. This goes beyond annotations without contradiction.

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 dense but not overly verbose. It front-loads the main purpose and then details output, cost, and behavior. It could be slightly more concise, but every sentence adds value.

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?

Given no output schema, the description thoroughly explains return values: per-call outcomes, true total, truncation flag. It also covers cost, persistence, and the handle parameter. This is more than sufficient for a simple tool.

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?

With 100% schema coverage and only one parameter (handle), the description adds meaning by explaining that the output includes per-call outcomes, true total, and truncation flag. This enriches the parameter's purpose beyond the schema's 'X handle, with or without @'.

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 clearly states the tool retrieves the most recent 100 measured Robinhood Chain calls for a given X handle, with per-call token outcomes. This distinguishes it from sibling tools like robinx_caller (individual caller info) and robinx_callers (list of all callers). The verb 'retrieves' and resource 'call log' are explicit.

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 usage via cost and persistence details, but does not explicitly state when to use this versus alternatives like robinx_caller or robinx_callers. It provides context (cost, record persistence) but lacks direct guidance on selection criteria.

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