login

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

Annotations only declare readOnlyHint=false and openWorldHint=true, so the description carries most of the burden and does well: it discloses that the result is a link requiring out-of-band user action and approval, which is the single most important behavioral fact about this call. It stops short of saying the session stays unauthenticated until that step completes.

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 short sentences with the action first and the return value second, no filler. Slightly more could be said about the follow-up step without bloat.

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 zero-parameter entry point into a multi-step auth flow with no output schema, the description sufficiently explains what comes back and what the user must do. The missing piece is how to detect approval afterwards (login_status / complete_login), which a sibling-aware agent can infer.

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 tool takes no parameters, so there is nothing for the description to disambiguate; baseline applies. The full burden shifts to behavior, which is covered elsewhere.

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 ('Start MyChart sign-in') and specifies what the call produces ('Returns a link the user must open'). The word 'Start' implicitly separates it from the sibling complete_login, though no sibling is named.

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 conveys that this initiates the flow and that a human must act on the returned link, which implies when to call it. It never explicitly says when to use it instead of login_status or complete_login, nor what to do after the user approves access.

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