teams_mark_read

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

Annotations already declare readOnlyHint=false with destructiveHint=false, i.e. a non-destructive mutation, which matches 'mark as read'. The description adds the default scope (newest message) but says nothing about whether read state is visible to other participants, whether it is idempotent, or how partial 'up to message' reads affect unread counts — relevant for an openWorld tool.

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, front-loaded with the action and its scope, then the usage cue. Nothing redundant or padded.

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 two-parameter, non-destructive mutation with no output schema, this covers what the tool does, its default behavior, and when to call it. The only gap is any mention of side effects visible to other chat participants.

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 50%: messageId is documented in the schema itself, conversationId is not. The description's 'mark a conversation as read ... up to a given message' implicitly maps both parameters, but adds no format or constraint detail beyond the schema's own wording.

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?

States a specific verb+resource ('Mark a conversation as read') plus the scope ('up to a given message'). No sibling performs a mark-read action, so it is distinguishable, though the description never names or contrasts an alternative explicitly.

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?

'Use after the user has reviewed the chat' gives a clear triggering condition for when to invoke it. It does not state when not to use it or whether it can be called repeatedly, but the usage context is clear and actionable.

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