get_channel_history

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

Beyond the readOnly/openWorld hints, the description discloses pagination support, default limits, acceptable date formats, thread-inclusion behavior, and boundary semantics for date-only values. This is materially richer than the annotations alone.

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 summary line is front-loaded, and the optional parameters are organized as a scannable list with examples. Every sentence adds value; the date-boundary note closes the one genuinely non-obvious behavior.

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 description covers all parameters, defaults, and date parsing in detail, and an output schema exists to explain return values. It leaves a small gap around how pagination actually works and how include_threads interacts with limit/date filters, but nothing blocks a competent agent from making a correct call.

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 carries full responsibility for documenting parameters, and it does so thoroughly: limit's meaning and default, oldest/latest formats with examples, and include_threads behavior. Only channel_id is left to the schema, where its name is self-explanatory.

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 opening sentence states the exact operation and resource: retrieving a channel's message history. It adds pagination and thread behavior, distinguishing it from thread-specific or search-based sibling tools even though it doesn't name them.

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 provides clear context: it is for fetching a channel's full history, with optional date filters and thread inclusion. It does not explicitly exclude search_channel_messages or get_thread, so it misses the 'when not to use' guidance that would earn a 5.

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