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

With no annotations, the description carries the full load and does so well: it discloses the no-key path, the dual return branches (address + supplier-listed 402 price vs. machine contract with assumptions, ledger-only reference price, and a funding question), the auth requirements for funding, and the observable post-funding state (funding.mode=prepaid, non-null funding.funded_at). It does not mention rate limits or failure modes, keeping it short of 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?

It is dense but front-loaded: the free path is stated first, then funding, then intake, then the funded-state invariant. Every sentence carries information, though the final sentence about funding.mode and funded_at is a niche detail that slows the close.

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 5-parameter, no-annotation, no-output-schema tool, the description is nearly complete: it explains the branching return values that an output schema would otherwise cover, plus auth and idempotency expectations. Only via_integration semantics and any error/permission behavior are left unaddressed.

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 60%, so the description must add meaning and it does: agent_key is 'required only with amount_usd', amount_usd is the funding trigger, and idempotency_key is paired with funding. The one gap is via_integration, which appears only in the schema and is never explained in prose.

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?

The description states a specific verb and resource ('send one demand sentence') and immediately explains the two possible outcomes: a capability address plus 402 price, or a machine contract. It is clear what the tool does, though it never names or contrasts against siblings like capability_call or bounty_post, so an agent must infer the boundary itself.

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 implied rather than framed: no key is needed for the basic send, and funding (amount_usd) requires agent_key plus idempotency_key. The 'when' for the funded vs. unfunded path is derivable from the sentence, but there is no explicit when-to-use-this-vs-alternatives guidance and no stated prerequisites for the 'validated contract' intake path beyond a passing clause.

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