pay-with-x402Before calling any Vybe endpoint without an API key (e.g. AI agent, throwaway script, premium-only path), use this to access the same endpoint via x402 pay-per-call USDC on Solana.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
| Name | Required | Description | Default |
|---|---|---|---|
| baseUrl | No | ||
| guidance | No |
Changes observed during successful MCP inspections.
Input schema / $schemaAdded value: +"https://json-schema.org/draft/2020-12/schema"Output schema / (root)Previous value: -nullNew value: +{
+ "additionalProperties": true,
+ "properties": {
+ "baseUrl": {
+ "type": "string"
+ },
+ "guidance": {
+ "type": "string"
+ }
+ },
+ "type": "object"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description usefully discloses the x402 pay-per-call USDC mechanism. However, the annotations declare readOnlyHint=true and idempotentHint=true, while a pay-per-call action that spends USDC implies a financial side effect and is not naturally idempotent. This is an annotation contradiction that could mislead an agent about the tool's side effects.
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 sentence with the triggering condition front-loaded and the action stated immediately after. It contains no filler, no repetition of the title, and every clause contributes useful selection guidance.
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?
Combined with the empty input schema and the presence of an output schema, the description provides the core selection and invocation context. It leaves operational details unstated, such as prerequisites like a Solana wallet or what happens if no endpoint is pending, and the annotation contradiction further reduces completeness and trust.
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 input schema has zero properties, so schema-description coverage is trivially 100%, giving a baseline of 4. The description adds no parameter-specific detail because there are none, though it hints at an implicit 'same endpoint' context without defining how that context is established.
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 action: use this tool to access a Vybe endpoint via x402 pay-per-call when no API key is available. The mechanism and resource are specified, and the 'without an API key' condition helps distinguish it from API-key-based call tools, though it does not explicitly name a sibling alternative.
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 an explicit when-to-use rule: before calling any Vybe endpoint without an API key, with concrete examples like AI agents and premium-only paths. It does not mention when not to use it or name alternative tools, but the context is clear and actionable.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.