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

Annotations provide readOnlyHint and openWorldHint. Description adds key behavioral trait: tool is paid and requires payment via x402, including flow to call without payment to get terms. Does not contradict annotations.

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?

Two sentences, no redundancy. First sentence gives purpose, second contrast with sibling and payment note. Every sentence adds essential information.

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?

Given no output schema, description adequately explains what the tool returns (which clients affected) and how to match results via ref field. Includes payment flow. Complete for a paid portfolio rescreening 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?

Schema covers 67% of parameters with descriptions. Description adds value by clarifying subjects parameter: 'Each needs at least a name or an ICO' and mentions batch cap. This supplements schema details.

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?

Description clearly states the tool re-screens a portfolio against sanctions changes since a date, specifying the resource (portfolio) and action (re-screen). It explicitly contrasts with sibling list_recent_updates, stating that this tool intersects global changes with user's list.

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?

Provides explicit guidance: 'Answers which of MY clients were affected, which list_recent_updates cannot'. Also describes payment requirement and advises to call without payment first to receive terms, indicating when-not-to-use.

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