A signature is the brand-specific pattern Cortex uses to score candidates. It is built from eligible winner and loser references.
Build requirements
To build a signature, the brand needs at least:
- 3 eligible winner references.
- 3 eligible loser references.
- No eligible references still processing.
Eligible means the reference is available, not excluded, and has a weight greater than 0.
What happens during a build
The build compares winners and losers and creates a brand-specific signature. When timeline data is available, Cortex also builds event-level comparisons for moments such as hooks, product shots, social proof, transformations, and CTAs.
The build also writes calibration and diagnostics outputs when there is enough reference data. These outputs help explain whether the bank is reliable and which blend of video-level and element-level scoring best separates known winners from known losers.
Build states
Signatures can be:
- Draft: no ready signature has been built.
- Building: a build is in progress.
- Ready: the latest successful signature can be used for scoring.
- Failed: the build did not complete. Review references and try again.
Only one active build should run for a brand at a time. If a build is already in progress, wait for it to finish before starting another.
Rebuilding
Rebuild a signature after meaningful reference changes:
- Adding new winners or losers.
- Changing a winner to a loser, or the reverse.
- Excluding a reference.
- Changing reference weights.
- Fixing failed or retried references.
New scorings use the latest ready signature. Existing scoring results remain historical and are not recalculated automatically.
Minimum buildable vs. reliable
The 3 winner / 3 loser threshold is the minimum to build. A small bank can produce useful direction, but confidence is limited.
More reliable banks usually have:
- More than 10 winners and 10 losers.
- Balanced counts across both sides.
- Similar ad formats and lengths.
- Clean labels.
- Good event coverage across hooks, proof, product shots, transformations, and CTAs.
Use calibration and diagnostics after the build to decide whether the bank is ready for high-stakes creative decisions.
When build is blocked
Common blockers:
- Not enough eligible winners or losers.
- References still processing.
- All references on one side are excluded or weighted to 0.
- The brand is archived or the workspace is read-only.
Fix the reference library first, then build again.