start_login

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

With no annotations provided, the description must carry the full behavioral burden. It does disclose the core behavior: opening a user-facing Chrome window for manual login. However, it does not mention whether the call blocks until login completes, what happens on cancellation, or how the agent knows the login succeeded.

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?

The description is a single, well-structured sentence that front-loads the condition ('when session is missing or expired') followed by the action. Every word adds value and there is no redundancy or filler.

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 parameterless tool with an output schema present, the description covers the essential purpose and trigger condition. The only notable gap is the lack of detail about post-call behavior (whether it waits, returns a session status, or raises an error), but the output schema may already document the return value.

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 has zero parameters and schema description coverage is 100%, so there is nothing for the description to add about parameter meaning. The baseline of 4 for parameterless tools applies, and the description correctly needs no parameter details.

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 the tool's action: it opens a Chrome window for the user to log in manually when a login session is missing or expired. This specific verb+resource combination makes it easy to distinguish from the sibling course/notice/assignment listing tools.

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 gives a clear triggering condition: use this when there is no login session or when the session has expired. It does not explicitly name alternatives or when-not-to-use, but the condition alone is sufficient given that the sibling tools are all data-retrieval operations requiring authentication.

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