getMessageLongtext

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

Beyond the readOnlyHint and destructiveHint annotations, the description adds meaningful behavioral details: per-language storage with no fallback, and that writing is not possible via ADT (PUT refused). These are valuable and not contradicting annotations.

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?

Three sentences, with the primary purpose front-loaded and no extraneous content. Efficient and well-structured.

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 read-only tool with no output schema, the description explains the return format (HTML), the language behavior, and the write restriction. It covers the key aspects needed to use it correctly, though it could mention the absence of fallback more explicitly as a usage caveat.

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 coverage is 100%, so the baseline is 3. The description adds no parameter-specific details beyond what the schema already provides, such as the zero-padding example for 'number' which is already 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 clearly states the tool reads the long text of one message in HTML form, with a specific verb and resource. It is unambiguous but does not explicitly differentiate from sibling tools like getMessages, so it falls short of a 5.

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?

The description implies this is for reading long texts (vs. short texts likely via getMessages), but it never explicitly says when to use this over alternatives, nor provides exclusions. The language fallback note gives context but not routing guidance.

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