search_channel_messages

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

With readOnlyHint and openWorldHint already present, the description adds useful behavior: Slack search API usage, in:<channel> filtering, sort semantics for timestamp vs score, and default limit. This goes beyond the annotations without requiring redundant safety disclosure.

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 compact and front-loaded, with a one-sentence purpose, a relevant API detail, and a clean Args list. Every line adds useful information without padding.

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?

Given the output schema exists and annotations cover safety, the description is nearly complete for correct invocation. It lacks only explicit guidance on adjacent tools like search_messages or get_channel_history, but nothing needed to call the tool correctly is missing.

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 0%, but the description compensates fully by explaining every parameter: channel_id, query, sort (with enum meaning), and limit (with default). This is essential because the schema titles alone would be insufficient.

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 and resource: search for messages within a specific channel. The Slack search API and in:<channel> filter make the scope explicit and distinguish it from general search_messages or get_channel_history.

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 clearly conveys this is for channel-scoped message search, which implies the right use case. It does not explicitly name alternatives like search_messages for cross-channel search, but the context is clear enough to route an agent.

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