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

The description discloses a real side effect that explains the non-read-only annotation: after payment the call 'gets their number', i.e., it provisions a phone number rather than being a pure read. It also describes the conditional 'ready' branch and what that response contains. It doesn't cover failure states or the privacy expectations of the status token beyond the schema.

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 the core action before the conditional detail about the ready state. The second sentence is long but every clause conveys distinct return content, so it earns its length despite being dense.

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?

With no output schema, the description carries the burden of explaining returns and does so well for the terminal state (number, swap instructions, pre-written messages). It is incomplete on the non-ready states - the enum of statuses and what a mid-setup response looks like is never spelled out.

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 description coverage is 100% - both setup_id and status_token are documented in the schema, including the 'Keep it private' note on the token. The description adds nothing about parameter format or provenance, so the 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?

Clear verb+resource: it reads setup progress and reports next steps. It even names the concrete payload (the new BuzzMeBro number and swap_the_buzzer steps) so an agent knows what the call yields. It stops short of explicitly contrasting itself with siblings like create_setup or check_building, which is why it isn't a 5.

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 phrase 'Once the person has paid' and 'says what to do next' implies this is the polling/status-follow-up call after create_setup, so usage is inferable. But there is no explicit when-to-call or when-not-to-call statement, no mention of polling cadence, and no named alternative.

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