Sign in to Google Flow

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

With no annotations, the description carries the full burden and does well: it discloses the visible side effect (a Chrome window opens and comes to the front), that the call blocks until user action, the early-return short-circuit, and that it consumes no credits ('Free'). It does not say what happens on timeout or what the failure mode looks like, which keeps it from a 5.

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?

Front-loaded with the core action, then the usage condition, then the user-facing pre-warning. The opening sentence is long and carries several clauses, but every clause (window start, foregrounding, waiting, return value) 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?

A single-parameter, zero-annotation interactive tool with no output schema; the description covers the interaction model, the trigger, the early return, and roughly what comes back ('the account'). Only the timeout/failure behavior and the exact return shape remain unspecified, which is a modest gap.

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 single parameter wait_seconds has 100% schema coverage including bounds and default, so the schema does the work. The description never mentions the wait duration or how the bounded wait interacts with the blocking behavior, adding no meaning beyond the schema; baseline 3 applies.

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 chain and resource: opens the Flow Chrome window, opens Google sign-in, waits for the user, returns the account. This is clearly an interactive authentication tool, distinguishable from siblings like flow_status (which only reports state) or flow_approve (which approves some other action).

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 names the trigger condition ('when flow_status says signed_out or on first use') and the alternative path ('returns at once if someone is already signed in'). It also prescribes an agent action before calling: tell the user a Chrome window will open and they should sign in.

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