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

Annotations already declare readOnly, idempotent, non-destructive behavior. The description adds substantive behavioral details beyond that: signed-zero stepping, infinity behavior, NaN payload preservation, pricing, and an HTTPS alternative. It still does not explain input precedence between bits and value or the full return shape.

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 front-loaded with the core operation and then gives concise edge-case and access details. Sentences are dense but purposeful, with no obvious repetition or filler.

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 4-parameter math tool with no output schema and 0% schema description coverage, the definition is only partially complete. It covers exceptional return values and pricing well, but leaves the main input parameters undocumented, which is a significant gap for correct invocation.

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 must explain all four parameters. It never mentions dir, bits, value, or width by name; only 'binary32 or binary64' loosely hints at the width enum. The bits and value string parameters remain completely opaque.

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 states a specific operation: returning the next binary32 or binary64 float value up or down. It clearly distinguishes edge-case semantics (zeros, infinity, NaN), but does not name or differentiate itself from siblings like float_ulp or float_order.

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?

It describes what the tool does but gives no guidance on when to use it versus related tools such as float_ulp, float_order, or float_round. The edge-case notes are useful but do not substitute for usage context.

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