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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description adds genuinely new behavioral facts: no key is required, no payment is executed by this tool, and tips confer no ranks, perks, visibility, or priority. It even clarifies the relationship to the underlying HTTP endpoint, which is exactly the kind of side-effect disclosure an agent needs.

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 front-loaded with the substantive answer (the tip methods) and the caveats follow compactly. The long parenthetical enumerating payment rails is dense but earns its place by telling the agent the exact return contents; only mild trimming is possible.

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?

There is no output schema to lean on, so the description must carry the return contents—and it does, listing each payment method plus network notes and the endpoint equivalence. Combined with the zero-parameter schema and full read-only annotations, an agent has everything needed to call and interpret this tool.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; the baseline for a no-param tool is 4. The listed tipping methods describe return content rather than inputs, which is appropriate here.

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 resource (tipping methods for the Pit) and enumerates exactly what it returns: card link, Bitcoin address, USDC on Base, x402 tip URLs, and network notes. It also identifies the backing endpoint (GET /v1/support), making it trivially distinguishable from the gameplay siblings like pit_move or pit_draw.

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 gives clear operative context—no key needed, nothing is paid through this tool, tips buy nothing—which tells the agent what to expect and that it should not be called as a payment action. However, it never states a triggering condition such as 'use when the user asks how to tip' or names an alternative to prefer in any scenario, so it stops short of explicit when/when-not guidance.

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