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

Annotations already declare readOnly, idempotent, and non-destructive, so the safety profile is covered. The description does add genuinely non-obvious behavioral context: a $0.001 USDC per-call price via x402 on Solana and an equivalent HTTPS endpoint. It still omits error/failure behavior and what happens for out-of-range or zero n.

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?

Three short sentences, front-loaded with the definition and an illustrative example, then bounds, then payment/transport details. Every sentence carries information, though the pricing/endpoint sentence is meta-infrastructure rather than definitional.

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 single-parameter, no-output-schema tool, the description supplies the return format ('string of 0 and 1'), a sample value, valid range, and cost. The only gap is the n=0 / boundary discrepancy between the stated range and the schema minimum.

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 0%, so the description carries the burden; it explains that n is the number of leading bits and bounds it at 1 to 4096, which the schema alone does not articulate. However, this conflicts with the schema's minimum of 0, leaving the boundary case genuinely ambiguous.

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 output (the first n Thue-Morse bits as a 0/1 string) with a concrete example, which is clearer than the bare name 'thue_prefix'. It does not name siblings like thue_morse, thue_sum, or thue_weight to explicitly disambiguate the prefix variant from those related tools.

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?

Usage is implied by the description — request n bits when a prefix of the sequence is needed — but there is no explicit when-to-use or when-not-to-use guidance relative to the many sibling sequence tools. The n range (1 to 4096) hints at valid scope but is not framed as guidance.

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