token_lookup

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

With no annotations, the description carries the full burden and does so: it discloses the paid model ($0.003/call, x402, USDC on Arc/Base/Solana or XNT on X1), that no key or sign-up is required, and — critically — that over MCP this tool returns the price and payment URL rather than the data. That last point is a non-obvious behavioral trait an agent could not infer from the schema.

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 core action and return fields, then routing, then payment terms. Dense but every clause carries information. The parenthetical payment-method list is slightly heavy, keeping it from a 5.

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?

No output schema exists, so the description must describe returns — and it does, listing price, holders, liquidity, volume and change. It also closes the biggest gap for a paid-over-MCP tool by stating that the MCP response contains a price and URL instead of data, so an agent is not surprised by the return shape.

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 100% and the single parameter is already documented as 'Symbol (e.g. CAPY) or mint address.' The description nonetheless adds real meaning beyond the schema: that a symbol yields the best search match and that a mint address should be preferred when tickers collide.

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?

Starts with a specific verb+resource ('Look up ONE X1 token by symbol or mint address') and enumerates exactly what is returned: price in XNT and USD, holders, liquidity, 24h volume and change. It explicitly distinguishes itself from sibling top_tokens, so an agent can route without opening a schema.

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 explicit when-to-use guidance: symbol returns the best search match, and when several tokens share a ticker the agent should run impostor_check first and pass the mint. It also names the alternative (top_tokens) for ranked lists. This is a complete routing decision.

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