iam_permissions__list_permissions

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds only that the listing is complete ("all possible permissions") and unparameterized by filters, which is modest extra context beyond the 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?

A single short line, front-loaded with the verb and resource, with no filler. The only redundancy is restating "list" twice ("List permissions" / "List all possible permissions").

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 endpoint with fully documented optional parameters and complete safety annotations, the description is adequate to select the tool. However, with no output schema, it says nothing about what a permission object contains or that results are paginated, leaving the agent to discover the return shape at call time.

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%, with fields, pageSize and pageToken each fully documented including defaults, maxima and projection behavior. The description adds nothing about these parameters, so the baseline of 3 applies when the schema does all the work.

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?

"List permissions" plus "List all possible permissions" gives a specific verb and resource, and the endpoint (GET /v2/permissions) confirms this is an unfiltered enumeration. It does not name or differentiate itself from the nearest sibling (iam_identity_provider__list_roles), so it stops short of a 5.

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?

There is no statement of when to use this versus alternatives, no prerequisites, and no mention of whether it should be called before other IAM operations. The agent must infer usage purely from the tool name and the phrase "all possible permissions."

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