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

Annotations already declare readOnly, idempotent, and closed-world behavior, so the safety profile is covered. The description adds meaningful context beyond the schema: arbitrary precision beyond 2^53, digit validation, input length cap, prefix handling, and a clear pricing model with payment rail. That last detail is important for cost-aware invocation.

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?

The description is one dense sentence followed by a payment note. It front-loads the core capability and scope, but the run-on structure packs multiple behavioral details into a single clause, which slightly reduces scannability.

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 five-parameter, no-output-schema conversion tool, the description covers the essential behavioral facts: precision guarantees, validation, input limits, and the return shape (target base, decimal, bit length, digit count). It is nearly complete, though it could explicitly note that invalid digits produce an error rather than a partial result.

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%, so all five parameters are documented with types, enums, defaults, and accepted values. The description adds context about sign and prefix handling for the value parameter, but does not add format or syntax details beyond what the schema already provides. Baseline 3 is appropriate.

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 (convert) and resource (integer between bases 2–36), and explicitly enumerates the scope (hex, binary, octal, arbitrary precision). The sibling tools are all unrelated operations, so the tool is unmistakably distinct.

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?

The description implies the tool's scope through examples but provides no explicit when-to-use or when-not-to-use guidance. For a tightly scoped numeric conversion utility, this is adequate but leaves the agent to infer that it is only for integer base conversion.

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