list_policies

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so the safety profile is covered. The description adds useful negative behavior ('does not read plans or invoke OPA'), which is genuine value beyond annotations, but it says nothing about cost, side effects on caches, or whether the policy set can change between calls.

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, zero filler. The positive scope comes first and the exclusions follow immediately, so an agent gets the useful content up front.

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?

An output schema exists, so return-shape explanation is unnecessary, and annotations plus the zero-param schema cover the rest. The description is nearly complete; a short pointer to evaluate_terraform_policies as the natural next step would close the only gap.

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?

Zero parameters, so baseline is 4. Both the description and the schema note that listing takes no filters, paths or configuration, which preempts an agent trying to narrow the result set.

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 the bundled governance policies') and scopes the result set ('available for Terraform plan evaluation'), then enumerates what the listing exposes. The closing sentence separates it from analyze_terraform_plan and evaluate_terraform_policies by denying plan-reading and OPA invocation.

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?

The phrase 'available for Terraform plan evaluation' plus the explicit exclusion of plan reading and OPA invocation steers an agent toward this as a discovery step rather than an execution step. It stops short of naming evaluate_terraform_policies as the follow-up call, so the routing is implied rather than stated.

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