Open WebUI MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions 'with pagination,' which hints at a paginated response, but fails to describe critical traits like whether this is a read-only operation, rate limits, authentication requirements, or what the output format looks like. For a tool with no annotation coverage, this leaves significant gaps in understanding its behavior.

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 a single, efficient sentence that front-loads the core purpose ('Get messages from a channel') and adds a key behavioral note ('with pagination') without any wasted words. It's appropriately sized for its function.

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 tool's moderate complexity (retrieving messages with pagination), no annotations, and an existing output schema (which handles return values), the description is somewhat complete but lacks details on usage context, parameter meanings, and behavioral traits. It covers the basic purpose but misses elements that would make it fully adequate for an agent.

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?

The schema description coverage is 0%, meaning parameters are undocumented in the schema. The description adds minimal value by implying 'channel' and 'pagination' context, but it doesn't explain the specific parameters (channel_id, skip, limit) or their semantics beyond what's inferred. With low schema coverage, the description doesn't adequately compensate, resulting in a baseline score.

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 action ('Get messages') and resource ('from a channel'), specifying the verb+resource combination. It distinguishes itself from siblings like 'get_channel' (which retrieves channel metadata) and 'post_channel_message' (which creates messages). However, it doesn't explicitly differentiate from 'get_chat' or other message-related tools, keeping it at 4 rather than 5.

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 no guidance on when to use this tool versus alternatives like 'get_chat' or 'list_channels', nor does it mention prerequisites such as needing channel access. It only states the basic function without context about appropriate scenarios or exclusions.

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