Mark chat as read

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

With no annotations provided, the description carries the full burden, and it does well by stating the mutating effects: sending read receipts and clearing the unread badge. It also scopes the action to 'recent' messages, but does not mention reversibility or rate limits; those are secondary for this operation.

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?

A single, front-loaded sentence with no filler. It efficiently captures the action, scope, and side effect in a way that is immediately useful.

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 two-parameter mutation with no output schema, the combination of description and input schema is sufficient for a correct invocation. The main gaps are explicit sibling differentiation and precise count semantics, but neither blocks a reasonable agent.

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%, with chat fully documented but count lacking a description. The phrase 'recent incoming messages' hints at what count might limit, but it doesn't explicitly connect count to the number of messages or explain the default/max behavior, so the description only partially compensates.

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 names a specific verb ('Send read receipts') and a concrete resource ('a chat's recent incoming messages') plus the observable outcome ('clear its unread badge'). This clearly distinguishes the tool from siblings like mark_as_unread or chat_unread.

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 the use case: when a chat has recent incoming messages and the user wants read receipts/badge cleared. However, it does not explicitly name alternatives or state when not to use this tool, leaving the agent to infer boundaries from sibling names.

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