automaton

web_extract__schema_extract

Pull specific named fields from a page (e.g. title, price, author). Price: $0.01 per call in USDC on Base (eip155:8453), paid with x402 in params._meta["x402/payment"]. HTTP: POST https://api.firstmention.uk/s/web-extract/schema-extract

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "url": "<url>"
    },
    "name": "web_extract__schema_extract"
  }
}

Input Schema

Name	Required	Description	Default
`url`	Yes
`fields`	No

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedNov 7, 2026
- addedInput schema / properties / url / format
```
Added value: +"uri"
```
- addedInput schema / required
```
Added value: +[
+  "url"
+]
```

Changed3 schema fields changedNov 6, 2026

addedInput schema / properties / fields / items
```
Added value: +{
+  "type": "string"
+}
```

removedInput schema / properties / fields / properties

Removed value: -{
-  "author": {
-    "type": "string"
-  },
-  "title": {
-    "type": "string"
-  }
-}

changedInput schema / properties / fields / type

Previous value: -"object"New value: +"array"

AddedNov 6, 2026

TDQS

A3.6/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations supplied, the description carries the full burden and does disclose the two most consequential behaviors: a $0.01 per-call cost in USDC on Base (eip155:8453) and the exact x402 payment location in params._meta. That is genuinely actionable context an agent cannot get from the schema. It stops short of describing failure behavior, e.g. what happens when a requested field is absent from the page.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The core purpose is front-loaded in the first clause, and the payment and endpoint details are compressed into two short sentences. The x402/HTTP block reads slightly like a raw data dump, but every element is functional rather than filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a paid, two-parameter tool with no annotations and no output schema, the description covers the payment prerequisite well but leaves the return shape and the optionality/behavior of `fields` unaddressed. An agent could invoke it, but not confidently predict the response when a field is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must compensate. The field examples ('title, price, author') do clarify the expected content of the `fields` array, which is real added meaning. However, it never says whether `fields` is optional, what happens if it is omitted, or whether entries are field names versus selectors, leaving meaningful ambiguity.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb and resource ('Pull specific named fields from a page') and gives concrete examples (title, price, author). It is clear what the tool does, though it never distinguishes itself from the closely named sibling web_extract__extract or webmd__extract.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is only implied: an agent can infer this is the tool to use when it knows which fields it wants rather than needing the whole page. There is no explicit statement of when to prefer this over web_extract__extract, web_extract__chunk, or webmd__extract, and no exclusions.

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

All automaton tools Inspect

Try in Browser

One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Glama MCP Gateway

Add one secure layer between your agents and this server.

Resources

Need Help?