slack_get_channel_history

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

With no annotations, the description must disclose behavioral traits but only states basic functionality. It doesn't mention whether messages include thread replies, rate limits, pagination, or authentication requirements. The channel parameter's behavior is underspecified given the schema's default null.

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?

Very concise with a clear one-line purpose and parameter list. The mismatch between 'required' and default null is a structural flaw, but overall efficient.

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 existence of an output schema, the description doesn't need to detail return format. However, it lacks operational context like pagination, time zone for timestamps, and channel scope requirements. The explanation of oldest format is helpful but incomplete.

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?

Adds some meaning beyond schema: channel is an ID, limit is max messages, oldest is a timestamp in Slack format. However, the description says channel is required while the schema allows null, creating confusion. Schema coverage is 0%, so the description 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?

States it fetches recent messages from a Slack channel, which is clear and distinguishes from other Slack tools like slack_get_thread_replies. However, the term 'recent' is somewhat vague without specifying the default time range, and the mention of 'channel (required)' conflicts with the schema's default null.

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 guidance on when to use this tool versus alternatives like slack_search_messages or slack_get_thread_replies. No prerequisites or context about required bot scopes are mentioned.

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