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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds domain context about what proxies do (forwarding and detokenizing), but says nothing about pagination behavior, result ordering, or rate limits beyond what the schema implies.

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 short sentences, front-loaded with the action and resource. The trailing 'Basis Theory: GET /proxies.' is marginally useful API mapping rather than agent-facing guidance, but it costs little.

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?

For a simple paginated list tool with a readOnly annotation and a fully-described schema, the essentials are present. Still, no mention of pagination behavior or return shape leaves minor gaps for an agent that has no output schema to consult.

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 100% — name, page, and size are each documented in the schema, so the description is not required to carry them. It correctly adds nothing redundant, but also contributes no extra filter syntax or pagination semantics.

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 (List) and resource (proxies), plus a helpful gloss on what a proxy is — 'forward requests to third parties, detokenizing in flight.' This distinguishes it from basis_theory_get_proxy in intent, though it does not name the sibling explicitly.

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 guidance, no prerequisites, and no mention of when to prefer get_proxy or other list tools. The agent must infer usage from the name alone.

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