Check available APIs for a target VRChat SDK version by reading the compatibility matrix to avoid using unsupported features.
WHEN: checking which APIs exist for a target SDK version. HOW: read the matrix before using version-specific features.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v2.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries full burden. It fails to explain how the target SDK version is determined since the input schema has zero parameters. This creates ambiguity about how the tool selects a version. It also doesn't disclose the return format or any side effects (though read-only is implied). The lack of clarification on the version mechanism is a significant behavioral transparency gap.
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 concise, using a WHEN/HOW structure that front-loads the key information. Every sentence earns its place, and there is no fluff. It's appropriately sized for a tool with no parameters, though it could be slightly more explanatory without losing brevity.
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?
For a zero-param tool with no output schema and no annotations, the description must fully explain how it works. It leaves the target SDK version mechanism unexplained, making it incomplete for an agent to call correctly. The description hints at usage but doesn't clarify what the tool returns or how the version is specified, so agent adoption would be hindered.
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 tool has zero parameters and schema coverage is 100% (empty), so baseline is 4. However, the description introduces an implicit 'target SDK version' concept without explaining how it's supplied, conflicting with the empty schema. This mismatch reduces the usefulness of the description for parameter understanding, so a 3 is appropriate.
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 states a clear purpose: checking which APIs exist for a target SDK version. It uses a specific verb ('checking') and resource (API matrix), and the WHEN clause provides context. However, it doesn't explicitly distinguish itself from sibling tools like search_sdk_feature, though the 'read the matrix' phrasing implies a lookup rather than a search.
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 explicit WHEN and HOW guidance: use it when checking API existence and read it before using version-specific features. This gives clear context for when to invoke it, but it doesn't mention alternatives or exclusions. The guidance is actionable and sufficient for most cases.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.