cohorts_list

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful behavior beyond annotations: the count is recalculated per request and can be null when the evaluation is unreachable. This is valuable runtime behavior an agent needs to interpret results correctly. No contradiction with annotations.

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 concise sentences, front-loaded with purpose. Every sentence earns its place: the first states what is returned, the second clarifies the dynamic count behavior. No filler or 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?

For a simple read-only list tool with one fully documented parameter and no output schema, the description covers the essential return content (cohorts, rules, person counts) and flags the nullable count edge case. Minor gap: it doesn't enumerate exact fields returned, but with no output schema the description does the job adequately.

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 coverage is 100% — the single projectId parameter is fully documented in the schema with a concrete example. The description adds no parameter-specific detail 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?

The description states a specific resource ('Cohorts of a project') and clearly describes what is returned: saved cohorts with their rules and current person counts. It's clear and distinguishable from the sibling cohort tools (cohort_create/update/delete/preview/export) by the verb 'list' in the name plus the explicit content. Not a 5 because it doesn't explicitly name the sibling it differs from.

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?

No guidance is given on when to use this tool versus alternatives. It does not mention that cohort_create/update/delete exist for mutations, nor does it give conditions for when listing is appropriate. The behavioral note about the count being recalculated is informative but not usage guidance.

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