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

With no annotations, the description carries the full burden. It usefully discloses two traits: the cost per call and the fact that a UUID is appended, which implies the output is non-reproducible across identical inputs. It omits what the returned structure looks like, which algorithm is used when the optional parameter is omitted, and any limits on input size.

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?

One front-loaded sentence plus a parenthetical cost note, with no filler. It could be marginally sharper by stating the default algorithm in the same breath, but nothing present is wasted.

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, non-destructive utility with no output schema, the description covers purpose, output composition, and price, which is close to sufficient. The gaps are the unspecified default algorithm and the undisclosed return format, both of which an agent would need before relying on the output.

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%, so both the text input and the SHA-1/SHA-256/SHA-384/SHA-512 enumeration are fully documented structurally, making 3 the baseline. The description adds only the general notion of SHA hashing and no per-parameter meaning, so it neither compensates for nor extends 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?

"SHA hash of text plus a fresh UUID" states a specific operation and resource, and the UUID detail meaningfully differentiates its output from adjacent text utilities like text_stats. It is clear enough that an agent can pick it over the listed siblings without opening the schema, though it never names a sibling explicitly.

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 guidance on when to choose this tool, no prerequisites, and no mention of alternatives among the seven sibling utilities. The only contextual remark is a billing note ("cost: 1 credit"), which does not help an agent decide whether to invoke it.

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