Unset Channel Message Reaction

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

Annotations already establish that the tool is a non-read-only, idempotent, non-destructive mutation. The description restates the action and mentions reply support, but that is also visible in the optional replyId parameter, so it adds little behavioral context beyond the structured data. No contradiction with annotations.

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 two short sentences with no filler, front-loading the core action and then adding the reply capability. It is appropriately sized for the tool's simplicity.

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 full schema coverage and rich annotations, the description is essentially complete: it identifies the operation and the reply variant, and the schema covers the required identifiers and reactionType. The lack of an output schema is not a gap because return values are not needed for invoking 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 description coverage is 100%, so the schema fully explains teamId, channelId, messageId, reactionType, replyId, and tenantId. The description does not add semantic meaning beyond the schema, so the baseline score of 3 is appropriate.

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 uses a specific verb and resource ('Remove a reaction from a message in a Teams channel') and explicitly extends to replies, which clearly distinguishes this tool from set_channel_message_reaction and unset_chat_message_reaction. The action is unambiguous even without opening the schema.

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 implies when to use this tool (whenever a reaction needs removing) but does not explicitly name the inverse tool set_channel_message_reaction or the chat variant, nor when to prefer one over the other. There are no stated exclusions or prerequisites, so guidance is adequate but implicit.

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