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

Goes well beyond the annotations: annotations only say it is a non-idempotent, non-destructive open-world write. The description adds that nothing is charged until the person pays, the two return paths (checkout link and x402Url), the wallet MCP scope required for agent payment, and the 401/OAuth behavior for guests.

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 purpose and return behavior, and every section earns its place. It is dense and parenthetical, however, with the offer catalogue and the wallet aside packed into long run-on sentences that slow scanning.

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?

An output schema exists, so return values need not be explained, yet the description still flags the two things an agent must act on (checkout link vs x402Url). Auth requirements, per-offer meaning, and payment consent are all covered, leaving nothing material missing for a purchase-initiating 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 100%, so the baseline is 3, but the description genuinely enriches semantics the schema defers to it for: it enumerates and explains each offer value, states that 'lang' sets the currency (pt in reais, the rest in dollars), and confirms 'report_id' is local-start only.

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 ('Start a purchase of a one-time INITE offer for the signed-in person') and immediately scopes it as one-time rather than subscription. It also distinguishes itself from lookalike siblings (inite_services, inite_book_call) by naming the concrete offers and the payment flow.

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 prerequisites and gating: 'Ask the person before buying; say the price' and 'Needs a signed-in inite.ai account: a guest call answers 401 and starts the OAuth flow.' It does not name a competing sibling for the same job, so the routing guidance is implicit rather than explicit.

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