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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds genuinely non-obvious behavior: indexes are zero-knowledge, so no stored text is returned — only ref_id, state classification and E-score — and the caller must map ref_id back to its own content. That is real context beyond the structured fields.

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?

Three short sentences, purpose front-loaded, with the surprising zero-knowledge return shape and the ref_id mapping action immediately following. No 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 no output schema, the description carries the burden of describing the return shape and does so well (ref_id, state classification, E-score). The only gap is pagination guidance, though limit/offset are self-documenting in the schema.

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 limit, offset and index_id are already documented in the schema (including the idx_ pattern and default 20). The description adds nothing about parameter behavior, so 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 ('Browse documents in a ColdState index'), which is legible against siblings like coldstate_search and coldstate_fetch. It stops short of explicitly contrasting itself with those siblings, so an agent must infer that this is unfiltered enumeration.

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: 'Browse' suggests enumerating an entire index rather than issuing a query, but the description never says when to prefer this over coldstate_search or coldstate_list_indexes, nor does it state prerequisites (e.g., that the index must already exist).

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