OpenFGA 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. While it indicates this is a permission check operation (which implies read-only behavior), it doesn't disclose important behavioral traits like whether this requires authentication, what the response format looks like, potential rate limits, or error conditions. For a permission checking tool with zero annotation coverage, this leaves significant gaps in understanding how the tool behaves.

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 with just one sentence that directly states the tool's purpose. There's zero wasted language or unnecessary elaboration. It's appropriately sized for what it communicates and is front-loaded with the essential information.

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 this is a permission checking tool with no annotations and no output schema, the description is incomplete. It doesn't explain what the tool returns (e.g., boolean result, detailed permission evaluation), doesn't mention authentication requirements, and provides no context about error handling. For a tool that likely returns important authorization decisions, this leaves too many unknowns for effective use.

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 provides no additional parameter information beyond what's already in the schema. However, with 100% schema description coverage where all 5 parameters have clear descriptions in the schema, the baseline score is 3. The description doesn't add any value regarding parameter usage, constraints, or relationships between parameters that aren't already documented in 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 tool's purpose as 'OpenFGA 권한 체크 - 사용자가 특정 권한을 가지는지 확인' (OpenFGA permission check - verify if a user has a specific permission). This is a specific verb ('check'/'verify') + resource ('permission') combination that distinguishes it from siblings like tuple operations or model management. However, it doesn't explicitly differentiate from 'openfga_list_objects' which might also involve permission-related queries.

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. With siblings like 'openfga_list_objects' (which might list objects a user has access to) and 'openfga_tuple_read' (which reads relationship tuples), there's no indication of when this specific permission check is preferred over those other approaches. The description only states what it does, not when it should be used.

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