Connect GCP

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

Adds substantial context beyond the annotations: propose-then-confirm two-phase flow, the exact credential sources it reads, that credentials stay on the machine, and that it never changes anything in GCP. This reconciles the seemingly odd readOnlyHint=false — the write is a local connection record, not a GCP mutation — so there is no annotation contradiction.

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 and the two-step flow before any examples; every sentence carries real information. The trailing example phrasings are mildly redundant with the prose but plausibly useful for matching user intent, so the cost is small.

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?

No output schema exists, and the description partially compensates by saying the no-arg call returns the visible open billing accounts. It does not describe what the connect call returns or what happens on failure (no credentials, multiple/zero accounts), which would matter for a 0-required-param setup tool.

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 coverage is 0% and billing_account_id has no description at all, so the description must carry the load — it does, explaining that omitting it lists accounts and setting it selects the one to connect. The only gap is the expected ID format (e.g. 0X0X0X-XXXXXX-XXXXXX), which an agent must infer from the listing output.

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 ('Connect a Google Cloud billing account') plus the scope of what it touches (existing local credentials, open billing accounts). The provider-specific wording lets an agent distinguish it from connect_aws and connect_azure without opening any schema.

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?

Gives explicit procedural guidance: call with no arguments to list accounts (nothing stored), then call again with billing_account_id set to connect one. It also states the prerequisite — credentials must already exist via GOOGLE_APPLICATION_CREDENTIALS or gcloud ADC — and supplies example user phrasings.

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