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 that the tool creates something with Python code, implying a write operation, but fails to address critical aspects such as required permissions, whether the creation is idempotent, error handling, or what the output looks like. For a mutation tool with zero 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 with no wasted words, clearly front-loading the core action and key details. Every part of the sentence contributes essential information, making it appropriately concise for the tool's complexity.

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 that there is an output schema (which should cover return values), the description doesn't need to explain outputs. However, as a mutation tool with no annotations and poor parameter documentation (0% schema coverage), the description is incomplete—it lacks behavioral context, usage guidelines, and detailed parameter semantics, leaving the agent with insufficient information to use the tool effectively beyond basic purpose.

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 0%, meaning none of the parameters (id, name, type, content) are documented in the schema. The description only vaguely references 'Python code' (mapping to 'content') and 'filter or pipe' (mapping to 'type'), but doesn't explain the purpose or constraints of 'id' or 'name', nor provide details on Python code requirements or type implications. It adds minimal value beyond the schema.

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 ('Create') and resource ('new function') with specific types ('filter or pipe') and implementation details ('with Python code'), making the purpose unambiguous. However, it doesn't explicitly differentiate from sibling tools like 'create_tool' or 'create_model', which would require more specific context about what distinguishes a function from those other entities.

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 provided on when to use this tool versus alternatives like 'create_tool' or 'create_model', nor are there any prerequisites, dependencies, or contextual cues mentioned. The description only states what the tool does without indicating appropriate scenarios or constraints.

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