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

With no annotations, the description carries the full behavioral burden. It helpfully discloses the return payload as hex plus base64 digests, which matters because there is no output schema, but it says nothing about the algorithm default (only the schema does), determinism, or any input size constraints.

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?

Two short sentences, zero padding, with the operation front-loaded and the return format following. Every clause earns its place; nothing is redundant prose.

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 two-parameter stateless utility with a fully documented schema, the description covers purpose and return shape well, which is exactly what is needed absent an output schema. The only minor gap is that no annotations exist to declare the operation non-destructive, though that is obvious for a hash function.

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 100%: both the 'algo' enum with its sha256 default and the 'text' parameter are documented in the schema itself. The description's algorithm list merely restates the enum values and adds no format or constraint detail beyond them, so the baseline 3 applies.

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 concrete verb ('Hash') plus resource ('a string') and enumerates the exact supported algorithms, so the agent knows precisely what the tool computes. It is unmistakably distinct from siblings like base64, generate_uuid, and generate_password, which are the only nearby tools that could be confused with it.

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 purpose (use it to hash a string), but there is no explicit statement of when to prefer this over alternatives such as base64 for encoding or generate_uuid for identifiers. No prerequisites or exclusions are offered, leaving routing to the agent's inference.

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