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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered by structured data. The description adds a genuinely behavioral detail beyond that: text is treated as UTF-8, which affects hash/encoding results for non-ASCII input. It does not mention the 200000-character input cap or failure behavior on malformed decode input.

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 sentence that front-loads the primary capability (hashing) and then the secondary one (encoding), with zero filler. Every clause carries information the agent needs.

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?

There is no output schema, so the description bears some responsibility for return-value semantics, yet it never says that hash operations return a hex digest, what the decode operations emit, or what happens on invalid input. For a two-parameter utility with strong annotations this is adequate but leaves a real gap around output form.

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 carry the meaning, and it largely does: it groups and names the twelve operation values and explains the semantics of the text parameter (UTF-8 input). The schema's maxLength of 200000 is left unexplained and the enum values themselves live only 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 states a specific verb+resource (computes cryptographic hash of text) and enumerates the exact algorithm families (SHA-1/256/384/512) plus the encode/decode operations (Base64, Base64URL, hex, URL). This is clearly distinguishable from siblings like text_stats or regex_test, and the stated capabilities map one-to-one onto the operation enum.

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 implicit: an agent can infer it should call this when it needs hashing or encoding, and no alternative tool in the sibling list overlaps meaningfully. However, there is no explicit when-to-use/when-not-to-use statement, no note on choosing among the twelve operations for a given intent, and no guidance on whether decode operations are the inverse of the encode ones.

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