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

With no annotations, the description carries the full burden and does real work: it clarifies there is no Kadaster submission, discloses the write-permission requirement on the API key, states the post-condition ('De order blijft payment_pending'), and quotes the exact rejection text for a stale quote. It does not address whether repeated calls can double-charge or what happens if payment initiation fails, which keeps it off 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?

Six short sentences, front-loaded with what the tool does and what it does not touch, then preconditions, then failure mode. Every sentence carries information an agent could not get from the schema or annotations.

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?

For a payment-mutating tool with no annotations, this covers preconditions, permission, the stale-quote failure path, and the resulting order state; an output schema exists so return values need not be described. The only real hole is the unexplained required job_id, which an agent must guess the provenance of.

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%, so the description must compensate, and it explains three of four parameters well: confirmed must be true, quote_hash comes from check_klic_price, and customer_total_eur must match the stored quote (with a mismatch surfacing as the stale-quote error). job_id is never explained, which is the one remaining gap.

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 de betaling van een gequote KLIC-melding') and immediately draws the boundary that matters most for this domain: 'Er gaat niets naar het Kadaster'. An agent can distinguish it from check_klic_price, which produces the quote this tool consumes.

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 an explicit gating precondition ('Alleen aanroepen nadat de gebruiker de laatste prijs expliciet heeft bevestigd') and points to check_klic_price as the source of quote_hash, which effectively describes the required call order. It stops short of naming a sibling to use instead or stating explicitly what to do when the precondition is unmet, so a 4 rather than a 5.

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