Open WebUI MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions wildcard support, which adds some context beyond basic functionality, but fails to describe critical behaviors such as whether the search is case-sensitive, how results are returned (e.g., pagination, format), error conditions, or performance implications. For a search tool with zero annotation coverage, this leaves significant gaps in understanding how it operates.

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 extremely concise and front-loaded, consisting of just two sentences that directly state the tool's function and a key feature (wildcard support). There is no wasted language, and every word contributes to understanding, making it efficient and easy to parse.

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 (search operation with one parameter), no annotations, and the presence of an output schema (which handles return values), the description is minimally adequate. It covers the basic purpose and parameter usage but lacks details on behavioral traits, error handling, and comparison with siblings, leaving room for improvement in guiding the agent effectively.

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 description adds meaningful semantics beyond the input schema, which has 0% description coverage. It specifies that the 'filename' parameter is a 'pattern' and provides an example with wildcards ('*.pdf'), clarifying usage that isn't evident from the schema alone. With only one parameter, this compensation is effective, though it doesn't detail constraints like pattern syntax or length limits.

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 purpose with a specific verb ('search') and resource ('files'), specifying it searches by 'filename pattern'. It distinguishes itself from the sibling 'list_files' by focusing on pattern-based searching rather than listing all files. However, it doesn't explicitly contrast with 'get_file' or 'delete_file', which slightly limits differentiation.

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 'list_files' (for unfiltered listing) or 'get_file' (for retrieving a specific known file). It mentions wildcard support, which hints at usage for pattern matching, but lacks explicit when/when-not instructions or named alternatives, leaving the agent to infer context.

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