I used the same url for two different postings.
Public attestation data feed JSON records ($0.0001 USDC)
| Name | Required | Description | Default |
|---|---|---|---|
| filename | Yes | Target attestation JSON filename (e.g. test.json) |
| Name | Required | Description | Default |
|---|---|---|---|
| data | Yes | Attestation JSON payload | |
| status | Yes | Attestation status |
Changes observed during successful MCP inspections.
Input schema / properties / filename / descriptionAdded value: +"Target attestation JSON filename (e.g. test.json)"Output schema / (root)Previous value: -nullNew value: +{
+ "properties": {
+ "data": {
+ "description": "Attestation JSON payload",
+ "type": "object"
+ },
+ "status": {
+ "description": "Attestation status",
+ "type": "string"
+ }
+ },
+ "required": [
+ "status",
+ "data"
+ ],
+ "type": "object"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations declare readOnlyHint, openWorldHint, and idempotentHint, which cover safety and idempotency. The description adds the cost ($0.0001 USDC) and explicitly says 'public', aligning with the openWorldHint. It does not contradict annotations, but it doesn't disclose other behaviors like rate limits or access requirements beyond the cost.
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 one concise phrase that conveys the core purpose and cost without excess. It is front-loaded with the resource type and includes the most critical operational detail (cost) in a single sentence. No filler words or redundant 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 the tool's simplicity (one required parameter, output schema present, harmless read-only operation), the description covers the essentials. However, it lacks differentiation from sibling feed tools and doesn't clarify what 'attestation' entails or any usage context. It's adequate but not fully self-sufficient for an agent choosing between similar tools.
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 schema description covers the filename parameter with an example (test.json), and coverage is 100%. The description adds no additional parameter meaning beyond what the schema already provides. Baseline of 3 is appropriate because the schema handles the parameter documentation.
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 the tool provides public attestation data feed JSON records, clearly identifying the resource and output format. The cost is mentioned, adding specificity. It doesn't explicitly differentiate from sibling tools like 'data_feeds' or 'x402_telemetry_feed', but the resource ('attestation data') is distinct enough for an agent to infer its purpose.
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. There is no mention of conditions, prerequisites, or exclusions. An agent must guess based on the name and description alone, which is insufficient given the presence of multiple feed-related siblings.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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