corroborate: how many independent sources say this?

Behaviour

Returns the DISTINCT hosts carrying this passage's story, grouped by source and ranked by host authority, and counts them.

The anti-hallucination check: one echoed rumour and an independently reported fact look identical in a result list, and different here. `independent_sources` counts every host that asserted the story, including hosts whose copy was folded into this one as a near-duplicate.

Check it before you state something as established.

Costs 2 credits; a call that runs and fails costs 1.

Arguments

inputSchema

Name	Type	Description
`id`required	string	Passage id to corroborate
`limit`	integer	—

Returns

A JSON payload in the text content block, and the same payload as structuredContent for clients that support it.

outputSchema

Name	Type	Description
`independent_sources`required	integer	Distinct hosts asserting this story
`merged_duplicates`required	integer	Copies folded into the survivor
`sources`required	object[]	—
`story_id`	string \| null	—

Calling it

Over Streamable HTTP, with the required arguments filled in:

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

Most clients do this for you — see Connect a client. To drive it by hand, complete the startup lifecycle first.

The same call over REST

If your client does not speak MCP, this capability is GET /corroborate, taking the same parameters and returning the same body.

curl -H "x-api-key: $UNLOB_API_KEY" \
  "https://api.unlob.com/corroborate?id=<id>"