login

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

With no annotations, the description must fully disclose behavioral side effects. It states it establishes an authenticated session and returns data, but omits critical side effects such as session persistence, cookie/token storage, or modification of saved credentials. Insufficient for a stateful mutation tool.

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, front-loaded with purpose and return values, followed by credential behavior. No unnecessary words or repetition; all content earns its place.

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 stateful login tool with no annotations and no output schema, the description is incomplete: it omits failure modes, prerequisites, side effects, and does not differentiate from sibling tools. An agent cannot fully predict the tool's impact or limitations.

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 covers all parameters at 100%, so baseline 3 applies. The description adds minor value by explaining the saved-credential fallback behavior for email and password, but otherwise repeats schema information.

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?

Clear verb 'establish' and resource 'authenticated browser session' with mention of login scenario and return values. Does not explicitly distinguish itself from sibling execute_scenario, but purpose is apparent from the login-specific scope.

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?

Offers no guidance on when to use this tool versus sibling tools like execute_scenario or explore_page. The credential fallback behavior is useful but does not help an agent choose between tools.

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