> ## Documentation Index
> Fetch the complete documentation index at: https://cxity.kairaxis.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Capture External Updates as Structured Signal References

> Preserve Slack updates, issue comments, and docs links as structured references with extracted signals — not injected into prompts.

Use external capture when something outside the codebase changes what the agent should do — a Slack direction from a PM, a customer escalation, a GitHub issue comment that redefines acceptance criteria, or a docs link that explains the API behavior you need to follow. Rather than pasting raw external content into model instructions, Contexity stores it as a structured, traceable reference.

## MCP Capture Shape

Agent hosts call `context_capture_external_reference` to record an external source. The call carries structured fields rather than raw text, so Contexity can label the source, extract signals, and apply the right trust level.

Here is a complete example payload:

```json theme={null}
{
  "source_type": "slack_thread",
  "locator": "slack://workspace/channel/thread/42",
  "title": "Profile RTL update",
  "source_summary": "PM clarified the profile dashboard must support RTL.",
  "source_trust": "user_direct",
  "verified": true,
  "signals": [
    {
      "signal_type": "requirement",
      "signal_key": "dashboard.profile.rtl",
      "summary": "Profile dashboard must be translated and RTL compatible.",
      "related_files": ["src/profile.rs"]
    }
  ]
}
```

Each field serves a specific purpose:

| Field            | Purpose                                                                         |
| ---------------- | ------------------------------------------------------------------------------- |
| `source_type`    | Categorizes the source — `slack_thread`, `github_issue`, `docs_link`, and so on |
| `locator`        | Points to the original source so it can be retrieved or cited later             |
| `title`          | A short human-readable label for the reference                                  |
| `source_summary` | A concise description of why this source matters                                |
| `source_trust`   | Indicates how reliable or authoritative the source is                           |
| `verified`       | Whether the signal reflects confirmed direction                                 |
| `signals`        | Structured takeaways extracted from the source                                  |

## Signal Keys

Use stable, dot-separated signal keys whenever a source describes something that may be updated later. A good signal key identifies the concern precisely and stays consistent across updates.

Good examples:

* `dashboard.profile.rtl`
* `billing.approval.flow`
* `ads.creative.generator.validation`

When a newer active signal uses the same key, Contexity supersedes the older one automatically. This means you don't accumulate conflicting versions of the same direction — the latest signal with that key wins, and the older one is marked as superseded.

## Safety Rules

Follow these rules to keep external context useful and safe.

<CardGroup cols={2}>
  <Card title="Do" icon="circle-check">
    * Summarize external content rather than quoting it verbatim
    * Include full provenance — source type and locator
    * Use stable signal keys for evolving product direction
    * Pass `related_files` when you know which files the source affects
  </Card>

  <Card title="Do Not" icon="circle-xmark">
    * Store raw secrets or credentials in any field
    * Turn external text directly into model instructions
    * Mark randomly imported content as `verified: true`
    * Hide or omit source provenance
  </Card>
</CardGroup>

<Warning>
  External text is treated as data, not instructions to the model. Contexity downgrades prompt-injection-like content to candidate needs-review context automatically. Do not attempt to use external capture as a back-channel for model instructions.
</Warning>