aws_login_start

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

Discloses that no browser is spawned from this process, which is important for an agent assuming a browser can be opened. Explains the external user interaction required and the need for a second call to complete login. Annotations are consistent.

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?

Three sentences, each serving a distinct purpose: describing the action, the output, and the follow-up. No unnecessary words. Highly efficient.

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?

Despite no output schema, the description explains the return includes a verification URL, short code, and sessionId (implied). It provides enough context for an agent to use the tool correctly. Differentiation from 24 sibling tools is clear. Minor gap: explicit return structure not stated.

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% with a clear description of the 'profile' parameter, including default behavior. The tool description does not add extra parameter details beyond the schema, but the schema is sufficient, so baseline of 3 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 starts an AWS SSO login via device-code flow, specifying the verb 'Start', resource 'AWS SSO login', and method 'device-code flow'. It distinguishes from sibling tools like aws_login_complete and aws_session_set.

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?

Explicitly tells when to use this tool (to initiate SSO login), how to surface the verification URL and code to the user, and the next step: call aws_login_complete with the returned sessionId. Provides clear flow guidance.

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