aws_list_profiles

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

Annotations already declare readOnlyHint true, destructiveHint false, and idempotentHint true. The description adds value by revealing the specific file source (~/.aws/config) and the exact return structure, going beyond what annotations provide. No contradictions.

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-load core information (what it does, what it returns) followed by usage guidance. No redundancy or unnecessary details.

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 tool with no parameters and no output schema, the description adequately covers purpose, return values, and usage context. Minor omission: potential error cases (e.g., missing config file) are not mentioned, but overall it's sufficient.

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 input schema has zero parameters with 100% coverage, so baseline is 4. The description doesn't need to explain parameters and instead focuses on return values, which is appropriate.

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 clearly states it lists AWS profiles from ~/.aws/config and specifies the returned fields (profile name, region, SSO metadata, isSso flag). It distinguishes itself from sibling tools by focusing solely on profile enumeration, not assuming roles or making API calls.

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 description explicitly defines three use cases: when the user hasn't named a profile, when they ask to switch profiles, or when an SSO-expired error mentions a profile you haven't seen. This provides clear guidance on when to invoke this tool versus alternatives.

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