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

The annotations already establish that this is a read-only, idempotent, non-destructive operation. The description adds useful behavioral context by stating that the guide covers what is imported, what is refused, and platform limits and terms.

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?

The description is a single, front-loaded sentence fragment that lists the guide's contents without unnecessary words. It is appropriately compact for a zero-argument reference tool, though the fragment style is slightly terse.

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 simple, read-only, zero-parameter guide tool with rich annotations, the description provides enough context about what the guide covers. It does not explain the return format, but no output schema exists and the content list is sufficient for correct invocation.

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?

The tool takes zero parameters, so there are no parameter semantics to explain. The schema is fully self-contained, and the description does not need to compensate for missing parameter details.

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 title 'Read the platform guide' and description 'Rules for writing a lambda' together make clear that this tool returns platform documentation. It specifies the content covered (returns, imports, refusals, limits, terms), but does not explicitly distinguish itself from sibling tools like read_lambda or create_lambda.

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 states what the guide contains but never says when to call this tool, when not to, or which alternatives exist. An agent can infer it is relevant while writing a lambda, but no explicit usage guidance is provided.

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