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

Annotations already cover read-only, idempotent, non-destructive behavior, so the description adds the genuinely new fact that the call is free and consumes no credits — a real cost signal for an agent planning call sequences. It also flags conditional availability ('when available') for the EIN add-on, warning the agent that a field may be absent. It stops short of describing caching, rate limits, or unsupported states.

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?

Single front-loaded sentence that opens with the verb and resource before listing outputs. It is dense but each clause (what is returned, pricing inclusion, EIN optionality, cost) adds information; the trailing 'Free; does not consume credits' is well-placed as a separate short sentence for emphasis.

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 an output schema and full annotations present, the description need not explain return shape, and it correctly focuses on scope and cost. The remaining gap is that it never indicates which states are supported or what happens for an unsupported state code in an openWorld tool — a real risk given the state parameter is free-text.

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% and the entityType enum is fully documented, so the schema carries parameter meaning. The description only adds the scoping constraint that the state is a single state ('in one US state'), reinforcing that this is not a multi-state query, but contributes no format or validation detail beyond the schema.

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?

Specific verb (Returns) plus precise resource (the intake checklist for forming an LLC or nonprofit in one US state) with the exact contents enumerated: required fields, state-specific questions, all-in pricing, EIN add-on. Clearly distinct from siblings like formation.compare or formation.checkout, which would be comparison or purchase rather than requirements retrieval.

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?

Usage is only implied — an agent can infer this is the pre-formation lookup step, and 'Free; does not consume credits' hints it is the cheap first call before formation.checkout. But no explicit when-to-use, no named alternatives (e.g. formation.compare for multi-state, formation.checkout for purchase), and no prerequisites stated.

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