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

The description discloses critical behavioral traits beyond annotations: it REPLACES the content body, requires baseUpdatedAt to be fresh (stale/fabricated values rejected with OUT_OF_SYNC), and explains the exact behavior of visibility settings (gm, masked, public) including that hidden pages are stripped from the world menu. This is rich behavioral context that annotations alone don't provide. The annotations (readOnlyHint=false, idempotentHint=true) are consistent with the description's PUT semantics.

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 dense but well-structured: it front-loads the core operation, then explains the replacement behavior, the baseUpdatedAt requirement, and visibility options. Every sentence adds value, though the visibility section is somewhat long. It's appropriately sized for the complexity of the tool.

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?

The description is complete for a complex update tool. It covers the replacement semantics, the concurrency requirement (baseUpdatedAt), the visibility options, and the append workflow. The output schema exists, so return values don't need explanation. The description gives an agent everything needed to call this tool correctly without guessing.

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 input schema has zero parameters, so the description carries the full burden of explaining what fields the caller must supply. The description explains the key fields: content body, baseUpdatedAt, and visibility. However, it doesn't enumerate all possible fields (e.g., name, maskName) explicitly, though it mentions maskName in the visibility explanation. With 0 params in schema, baseline is 4, and the description adds substantial meaning about the required fields.

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 operation: 'PUT updates to one world page by id.' It specifies the resource (world page), the method (PUT), and the scope (one page by id). It also distinguishes itself from siblings like imagine_update_world and imagine_update_adventure_page by explicitly naming the resource type.

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 provides explicit when-to-use guidance: it explains that to append content, you must first fetch the page with imagine_get_world_page, concatenate, and send the combined body. It also states the requirement for baseUpdatedAt from a fresh read, and explains the visibility options. This is strong usage guidance that tells the agent exactly how to use this tool correctly.

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