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

Annotations already establish read-only, non-destructive, open-world behavior. The description adds useful behavioral context by disclosing the return shape ('verified current public text and citation URL') and emphasizing that the content is current. No contradiction with annotations exists.

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, well-structured sentence front-loads the action and resource, then states the output. Every phrase earns its place, and there is no redundant or vague filler.

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 one-parameter read tool with readOnly and openWorld annotations, the description covers the source of the id and the return value. It does not explain failure modes or URL format details, but the tool's low complexity means the description is largely 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?

Schema coverage is 0% and the only parameter is an undocumented 'id'. The description compensates by linking that id to the canonical public URL returned by search or list_public_pages, giving the agent a concrete way to obtain and understand the parameter. It stops short of fully explaining the expected URL format, but is sufficient for a one-parameter tool.

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 action ('Fetch'), a specific resource ('canonical public URL returned by search or list_public_pages'), and the expected output ('verified current public text and citation URL'). It clearly distinguishes this tool from siblings like search and list_public_pages by positioning fetch as the follow-up retrieval step.

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 gives clear context: the canonical URL must come from search or list_public_pages, which tells an agent when fetch is appropriate. It does not explicitly list exclusions or alternatives, but the source constraint effectively routes the tool relative to its siblings.

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