cksum

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

Description states 'Read-only, no side effects' and 'Returns JSON', adding context beyond readOnlyHint annotation. Annotations already indicate read-only, but description adds output format and no side effects, which is useful.

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?

Four sentences, each necessary: purpose, output description, usage guideline, security warning. No fluff, information front-loaded.

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 checksum tool with no output schema, description covers purpose, usage, security context, read-only nature, and return format. Complete given the tool's complexity.

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?

Input schema has 100% coverage with descriptions for both parameters. Description adds meaning by clarifying that paths can be stdin with '-', and defaults to stdin, providing context beyond the schema.

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?

Clearly states the verb 'Compute', resource 'CRC32 checksums and byte counts', and input 'files or stdin'. Distinguishes from siblings by naming alternatives like sha256sum.

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?

Explicitly says 'Use for fast data-transmission integrity verification' and 'Not for cryptographic security — use sha256sum or b2sum', providing clear when and when-not with alternatives.

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