setup_auth

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

With no annotations provided, the description carries the behavioral burden and does so well: it explains the browser window opens, the tool returns immediately, the user has 10 minutes to log in, and get_health should verify success. It could go further by specifying what happens if the login times out or whether existing credentials are overwritten, but it is still notably transparent.

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 well-organized and front-loaded with the core behavior, then alternatives, then troubleshooting. It is longer than minimal but every section earns its place, especially the troubleshooting block that tells an agent exactly how to recover from auth failures.

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 annotations and no output schema, the description covers the main operational context: what it does, how long login takes, how to verify success, when to use an alternative, and how to recover from persistent failures. Minor gaps remain around exact return behavior and edge cases like expired browser sessions, but overall it is complete enough to call correctly.

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 already provides 100% parameter coverage, describing show_browser and browser_options with defaults and guidance. The description itself does not add significant parameter-level meaning, but that is acceptable because the schema is already rich and the baseline for full schema coverage is 3.

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 purpose: Google authentication for NotebookLM access via a manual browser login. It also explicitly contrasts setup_auth with re_auth, so an agent can distinguish them without opening schemas.

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 concrete usage guidance: use setup_auth for first-time authentication or when auto-login credentials are unavailable, use re_auth for account switching/rate-limit workarounds, and verify with get_health afterward. It even includes a troubleshooting sequence involving cleanup_data, which fully covers when and how to use this tool.

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