slack_thread

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

No annotations are provided, so the description carries the burden. It discloses that the tool returns both the parent message and all replies, and explains how limit and resolve_names work. However, it does not mention rate limits, auth needs, pagination behavior, or edge cases like invalid thread_ts, which would be useful.

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 concise, front-loaded with the main purpose, and each argument is explained in one line. No redundant fluff.

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?

The tool has an output schema, so return values are likely covered there. The description covers purpose and parameters adequately. It lacks explicit guidance on alternatives and edge cases, but for a simple fetch tool, it is fairly complete.

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?

With 0% schema description coverage, the description's argument explanations add valuable meaning. For example, it clarifies that thread_ts is the timestamp of the thread parent and can come from a previous result's ts field. This goes beyond the schema's simple titles.

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 tool's function with a specific verb ('Fetch') and resource ('every reply in a thread, including the parent message'). This distinguishes it from sibling tools that handle channel or DM history, as it is specifically for thread replies.

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 tool is for fetching thread replies but does not explicitly compare it to siblings like slack_channel_history or slack_search. There is no mention of when to use this over alternatives or any exclusions, so usage guidance is only implied.

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