SPIKE: ML Tagging – CAPI → Commercial → Prebid Integration

[dskamiotis]

Context

Data Science are building an automated pipeline that assigns IAB Content Taxonomy tags to Guardian articles.

Commercial could use these tags for contextual targeting via Prebid / GAM.

Before implementation we need to determine how these tags move through the stack.

Pipeline under consideration:

flowchart TD
    A[CAPI<br/>IAB Categories]
    B[dotcom-rendering<br/>frontendData]
    C[Commercial Bundle<br/>Targeting config]
    D[Prebid / GAM]
    E[Demand Partners]

    A --> B --> C --> D --> E

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Questions to answer

1. Data contract

Where will IAB tags appear in the CAPI response?

Example possibilities:

• content.metadata.iabTags
• content.tags

Questions:

• structure of tags (string / id / tier)
• number of tags per article
• primary vs relevant tags

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2. CAPI → Frontend pipeline

Verify whether tags are already exposed in frontendData.

Possible path:
CAPI → DCR → window.guardian.config.page

If not, identify required change.

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3. Commercial integration

Determine how tags should be exposed to the commercial bundle.

Possible location:
window.guardian.config.page.iabTags

Ensure availability before ad initialisation.

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4. Vendor targeting

Determine how tags should be passed to demand partners.

Options:

Prebid ORTB2

pbjs.setConfig({
  ortb2: {
    site: {
      content: {
        cat: ["IAB1"]
      }
    }
  }
})

GAM key-values

Example:
iab=sports_soccer

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5. Experimentation

Determine whether tagging should initially be rolled out behind:

• feature flag
• A/B test

Metrics:

• CPM
• Fill rate
• Bid density

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Potential follow-up work

These will likely become separate implementation issues once the spike confirms the design.

• Expose IAB tags in CAPI / frontendData
• Surface tags to the commercial bundle
• Integrate tags into Prebid configuration
• Determine GAM targeting strategy
• Implement experiment / feature flag

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Expected output of this spike

• confirmed data schema
• defined pipeline from CAPI → Commercial
• recommendation for vendor integration
• list of implementation issues