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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds genuinely non-obvious behavioral context: slug and revision_id must match, a mismatched pair returns NOT_FOUND, and revision ids are not probeable across pages. This materially changes how the tool can be used.

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?

Two short sentences deliver the core purpose, the auth requirement, and the critical validation rule without wasted words. The most important information is front-loaded.

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?

With an output schema present, no nested objects, and read-only annotations already provided, the description covers the essential remaining context: auth, exact fetch target, and the non-obvious error/scoping behavior. Nothing critical is missing for calling this tool correctly.

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 real value by explaining that the two parameters are validated together and that a mismatched slug/revision_id pair produces NOT_FOUND, which helps the agent understand the interaction between slug and revision_id beyond their individual schema descriptions.

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 opens with 'One past revision, with its full content snapshot,' which states the exact verb and resource, and clearly differentiates this from getting the current page or listing a wiki history. Saying 'No auth required' adds an important access-level distinction.

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: this tool fetches a specific past revision and requires no auth. However, it never explicitly names alternatives such as colony_get_wiki_page for current content or colony_wiki_history for listing revisions, so when-to-use-versus-alternatives guidance is only implied.

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