set_page_emoji

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

Annotations already indicate idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds the useful behavior of clearing the emoji with an empty string, which is not captured in annotations. However, it does not describe overwriting behavior or any side effects, so the added value is moderate.

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 exactly two sentences with no redundant words. It front-loads the primary purpose and adds the clearing nuance in a concise second sentence. Every word earns its place.

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 mutation tool with no output schema, the description is incomplete because it does not explain what pageId and collectiveId refer to. It also omits any prerequisites or consequences (e.g., overwriting an existing emoji). Given the low schema coverage, an agent is left without enough information to correctly construct a call.

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 description coverage is only 33% (only the emoji parameter has a description). The description does not compensate for the missing descriptions of pageId and collectiveId. It repeats the emoji clearing behavior already present in the schema, but provides no additional meaning for the other two required parameters.

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 action: 'Set the single-emoji icon on a page.' This uses a specific verb and resource, and explicitly mentions 'page' to distinguish from similar tools like set_template_emoji. The additional instruction about passing an empty string to clear further clarifies the behavior.

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 clear context that this tool is for setting an emoji on a page, but it does not mention any alternatives or when not to use it. It fails to differentiate from the closely related set_template_emoji, so an agent has no guidance on choosing between them beyond the resource name.

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