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

With no annotations, the description carries the full behavioral burden. It usefully discloses that computation is local with no upstream call (relevant for hashing sensitive input), but omits return format, determinism, error behavior, and how the `text` parameter is treated by the uuid op, leaving significant behavior undisclosed.

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?

A single tight sentence that front-loads the core capability list and closes with the no-upstream caveat. No filler or repetition.

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 four-operation utility with 0% parameter documentation and no output schema, the description is incomplete: it never resolves the SHA-256 vs SHA-512 choice (unrepresentable in the schema), never explains `text` semantics per op, and says nothing about the shape of results.

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 compensate. It explains the op values implicitly by naming the operations, but never documents the `text` parameter (required for hash/base64, presumably ignored for uuid) nor how an agent selects SHA-256 vs SHA-512, since no algorithm parameter exists in 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?

The description gives a specific verb+resource ('Run local cryptographic utilities') and enumerates the exact capabilities (SHA-256/SHA-512, Base64 encode/decode, UUID v4), so an agent knows precisely what it does. No sibling (domain-lookup, fx-rates, etc.) competes with it, so explicit differentiation isn't needed, but the description also doesn't reference its siblings at all.

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?

There is no explicit when-to-use or when-not-to-use guidance, nor any mention of alternatives. The only contextual hint is 'No upstream service is called,' which implies suitability for offline/local cases but never states it as a usage condition.

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