slack_read_messages

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

No annotations are provided, so the description carries the behavioral burden. It signals a non-mutating read operation and scopes to 'recent messages,' but it does not disclose ordering, whether thread replies are included, or pagination behavior beyond schema parameters. This is adequate for a simple read but not rich.

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 one concise sentence with no filler. The main action is front-loaded, and the supported channel formats immediately follow. Every clause earns its place.

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?

All parameters are documented in the schema and the primary purpose is clear, but there is no output schema and the description does not clarify what the returned message data looks like or how it differs from reading a thread. For a simple read tool this is acceptable, though more context would improve selection confidence.

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 100%, so the schema already documents all five parameters. The description repeats the channel format guidance rather than adding new semantic detail, which matches the baseline score for fully covered parameters.

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 uses a specific verb and resource: 'Read recent messages from a Slack channel, DM, or group chat.' It clearly identifies what the tool operates on and supports distinct addressing forms (#channel, @username, channel ID), which sets it apart from siblings like send, react, search, and list tools.

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 is given about when to use this tool versus alternatives such as slack_read_thread or slack_search. The description does not mention exclusions or direct users to a sibling tool for thread replies or search, so the agent must infer the appropriate choice.

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