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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description's real added value is the price disclosure ('0.003 USDC'), which is genuinely useful behavioral context, but it says nothing about return shape, detection thresholds, or what counts as a duplicate.

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?

A single front-loaded sentence with zero filler; the detection target leads and the cost trails. Nothing is wasted.

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 one required parameter and annotations covering safety and idempotency, the definition is nearly callable, but with no output schema the description should say what a detection result looks like (matched pairs? boolean? report?) and it does not.

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 0% and the single 'charges' parameter is typed only as an array of bare objects, so the schema gives almost nothing. The description partially compensates by naming the identifiers being compared (transaction hashes, payment identifiers, intents), but it does not define the item fields the example implies (amount, network, recipient, transaction).

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 ('Detect') and enumerates the resource being detected: repeated transaction hashes, payment identifiers, and idempotent intents. Clear on its own, but it does not differentiate itself from adjacent payment tools like payment_diagnose or payment_receipt_reconciler, so an agent must infer the boundary.

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?

No when-to-use or when-not-to-use guidance, and no alternative tool is named despite ~28 payment-related siblings. The phrase 'idempotent intents' hints at a retry/double-spend scenario but never states the trigger condition explicitly.

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