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

Annotations already cover the safety profile (readOnly, non-destructive, closed-world), and the description adds genuinely new behavioral context: results are tier-dependent, with signed-out or sub-Professional callers receiving only code/name/description and no provider or criteria counts. It does not mention ordering, pagination, or result size, which keeps it out of the top band.

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?

Two sentences, front-loaded with the payload description and then the access/tier caveat. The second sentence restates part of the first ('code, name and description only') to draw the contrast with full results, which is a minor repetition but it earns its place by clarifying the downgrade behavior.

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 parameters and no output schema, the description carries the full burden of describing returns, and it does so well — field list, tier-dependent variation, and auth requirements are all covered. Only minor omissions remain (ordering, whether counts are always integers, total module count).

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 there is nothing to document and the baseline is 4. The description cannot add parameter meaning beyond the empty schema.

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 ('List ACI Risk Indicator modules') and enumerates the return fields (code, name, description). The resource is clearly distinct from siblings like get_provider_detail or search_providers, but the description never explicitly contrasts itself with them, so it stops short of the top band.

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 — an agent reading it understands this is the catalog listing for modules, and the 'no sign-in needed' note signals it can be called unauthenticated. There is no explicit statement of when to use this versus alternatives, nor any exclusions.

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