Evidence

A signal is an event. Evidence is a signal bound to a claim, a source and a date, so that the claim can be checked by somebody who does not trust it. Everything the system decides is built out of evidence records, and nothing else is allowed to influence a verdict.

The rule#

This is stricter than it sounds, and it is the constraint that makes the rest of the system usable. It means you can disagree with a decision by opening one link. It means the messages Nexus drafts can only reference things that are actually true about the company. And it means the system cannot quietly develop confident opinions with nothing underneath them.

Anatomy of an evidence record#

Every record has the same shape whether it came from a filing, a careers page or a CRM field.

idstringrequired

Record locator, e.g. EV-2291. Stable, and quotable in support conversations.

claimstringrequired

One sentence, in plain language, stating what is believed to be true. Not a summary of the source — the specific assertion being made.

kindstringrequired

The signal family. Determines the decay rate and how the record counts toward stacking.

strengthstrong | moderate | weakrequired

How much the source actually supports the claim. See below.

citation.sourcestringrequired

What kind of source it is — a filing, a careers page, a registry, a case study. Shown before the URL because the type tells you how much to trust it.

citation.urlstringoptional

Where to go and look. Absent only for sources that have no public address, such as a value read from your own CRM.

citation.observeddaterequired

When the system saw it. Distinct from when the event occurred, which is stored separately when the source states it.

confidenceinteger 0–100optional

How sure the extraction is that the claim follows from the source. Low confidence with a strong source usually means ambiguous wording, not a weak fact.

Strength#

Strength grades the relationship between the source and the claim — not how exciting the claim is. A dramatic claim from a vague source is weak evidence.

Weak evidence is kept, not discarded. It cannot carry a verdict alone, but it can corroborate, and it can supply a detail worth mentioning in a message once the verdict has been reached on stronger grounds.

Where evidence comes from#

Sources are ranked by how directly they speak for the company. When two sources disagree, the higher-ranked one wins and the conflict is recorded rather than silently resolved.

• Regulatory and registry filings. The company said it to a regulator. Highest weight available.
• The company’s own site. Careers pages, location pages, published commitments, changelogs.
• Public records about the company. Planning records, licence registers, procurement notices.
• Third parties naming the company. Vendor case studies, partner directories, conference programmes.
• Your own systems. CRM fields, past conversations, meeting notes. Treated as strong for facts about your relationship and weak for facts about the market.

A decision usually rests on several records at once. The stack below is what supported one qualification — three families, one quarter, one shared rail because they support one decision.

Verification and expiry#

Evidence is re-checked on a schedule tied to its family. Re-checking does three things: it confirms the source still exists, it detects when the claim has changed, and it re-dates the record if the source itself has been updated.

A superseded record is never deleted. It stays attached to the decisions it influenced, so a decision made six weeks ago can still be explained on the evidence that existed at the time — which is the only fair way to review it.

{
  "id": "EV-2291",
  "state": "changed",
  "claim": "Northwind Freight opened its first Head of Operations role.",
  "kind": "hiring",
  "strength": "strong",
  "citation": {
    "source": "Careers page",
    "url": "https://example-northwind.test/careers/head-of-operations",
    "observed": "2026-06-19"
  },
  "superseded_by": "EV-2402",
  "superseded_reason": "Role listing removed; no replacement posting found.",
  "affects_decisions": ["DEC-4417"]
}

Next: the buying window — what all of this evidence is being used to detect.