mark_read

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

The description only mentions 'best-effort' which hints at unreliable behavior, but does not elaborate on failure conditions, side effects, or required permissions. With no annotations provided, the description carries full burden but falls short.

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 very brief (one sentence), which is concise but at the cost of missing critical details. It could be expanded slightly to cover parameter guidance and usage without becoming verbose.

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?

Despite low tool complexity (one required param, no nested objects), the description lacks completeness. It does not explain return values, behavior under failure, or how the 'best-effort' nature impacts the agent's decision. The existence of an output schema is mentioned in context signals, so return values are partially covered, but the description adds little.

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 only parameter 'chat' is described only by its schema (type string, required). The description adds no information about format, source, or meaning beyond the schema. Given 0% schema description coverage, the tool definition provides no help for agents to construct valid input.

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 ('mark read') and the resource ('chat'), and includes the scope ('through macOS Messages'). It implicitly distinguishes itself from siblings like get_unread_messages or send_message by specifying a mutation action.

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?

No explicit guidance on when to use or not use this tool, no mention of prerequisites or alternatives. The 'best-effort' qualifier hints at limitations but doesn't clarify when it might fail or suggest other tools.

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