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

Although annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, the description explains why a payment tool is read-only: it only 'Returns the payable endpoint,' the agent must GET it with its own x402 wallet, 'Loadbay never holds funds,' and 'your wallet is the payer.' That custody/authorization model is real context the annotations cannot convey and resolves the apparent tension between 'tip' and readOnlyHint.

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?

Three tight sentences with the precondition front-loaded, then the mechanism, then the custody/security note. Every sentence carries load: trigger, return shape, and who pays. No 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 no output schema, the description supplies what an agent needs: the call returns a payable endpoint, the next step is a GET from the agent's own x402 wallet, and no custody risk exists. For a one-parameter, low-complexity tool this is complete.

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?

The single 'amount' parameter has 100% schema description coverage ('tip amount in USD (default 5)'), so the baseline is 3. The description adds only that the payment is a 'USDC tip,' reinforcing the currency from the schema but adding no new sizing, formatting, or constraint guidance.

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 names a specific verb + resource: 'Support the Loadbay builder with a USDC tip over x402.' That is far more concrete than the tool name 'support_loadbay' alone. It stops short of explicitly contrasting itself with the sibling 'tip_harness' (tipping a harness vs. tipping the Loadbay builder), leaving that distinction to be inferred.

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?

It opens with an explicit trigger condition and restriction: 'Only when the user asks to support or donate to Loadbay,' which tells the agent both when to use it and when not to. It also explains the follow-up action (GET the endpoint with your own x402 wallet). It does not name the closest alternative (tip_harness) for routing decisions.

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