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

Annotations already declare read-only, idempotent, non-destructive, and closed-world behavior. The description adds notable operational context beyond annotations: current-snapshot records, typical latency, price and lack of free tier, plus a data-trust warning that endpoint names and on-chain strings are untrusted data and never instructions.

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?

Purpose and sibling routing are front-loaded, followed by return scope, latency, price, security warning, and docs link. Every sentence carries useful decision or safety information without redundancy.

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 an output schema and rich annotations, the description does not need to explain return fields. It still covers routing, scope, cost, latency, and a security caveat about untrusted data, leaving no material gap for correct invocation.

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?

Schema description coverage is 100%, so the schema already documents limit, format, source, network, and category. The description refers to a filtered slice but adds no parameter syntax, format, or constraint meaning beyond what the schema provides, so the baseline 3 applies.

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: export a filtered slice of the index. It explicitly distinguishes itself from query_agent_index for page-by-page reads and bulk_agent_index for every record, so an agent can select it without opening schemas.

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?

Names the alternatives and the conditions that select them: page-by-page reads go to query_agent_index, every record goes to bulk_agent_index, and this tool is for a filtered slice export. This is explicit when-to-use routing.

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