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

Annotations only declare safety/idempotency flags; the description adds materially more: this is a paid tool costing $222.00 in USDC on Base or Arbitrum One, requires an x402 v2 PAYMENT-SIGNATURE header, and returns a signed Outcome Receipt. Payment mechanics and cost are exactly the kind of behavioral context annotations cannot carry. It does not describe failure/refund behavior or latency, keeping it from 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?

Front-loaded with the use case, then payment/auth mechanics and the paid URL. Every sentence carries information (capabilities, transport, payment, price). It is dense but not padded; only the bare docs link is low-value filler.

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 present, return values need not be explained. The description covers the essentials an agent needs to invoke a paid, non-idempotent-looking-but-idempotent tool: what it does, how to pay, where to POST. Error handling and what the receipt contains are left implicit, which is a minor gap.

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 idempotency_key description in the schema is unusually thorough (replay semantics, per-tool/per-payer scoping). The description adds no parameter-level detail beyond the schema, so the baseline of 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?

States a specific composite capability: URL liveness, content verification, TLS fingerprint, x402 trust verdict, and document timestamp composed into a signed Outcome Receipt. That is far more specific than the name 'diligence_pack' or title 'Compute History' (which arguably misleads), and it is distinguishable from single-purpose siblings like trust_report or assurance_check. It stops short of explicitly contrasting itself with those siblings, so not 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?

Gives an explicit trigger: 'Use diligence_pack when you need the full proof suite in one call', which implies the alternative is calling the individual checks separately. It does not name those alternatives or state when NOT to use this (e.g. for a single check, or when budget matters), so it is clear context without exclusions.

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