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title: "Parity" description: "Projection-based parity checks used to compare codex output with external baselines." group: "Reference" order: 5

Parity

Parity verifies that codex output matches an expected projection shape.

Profiles

• summary — core viewer essentials (version, page count, encryption, boxes)
• inventory — aggregate and per-page inventory counts
• deep — expanded conformance/trapping/count snapshots

Output

Parity writes a JSON report with:

• profile
• fixture set
• per-file case results
• diff list per case
• total diff count

Typical workflow

uv run codex-pdf parity --fixtures-root tests/fixtures --profile summary
uv run codex-pdf parity --fixtures-root tests/fixtures --profile inventory
uv run codex-pdf parity --fixtures-root tests/fixtures --profile deep

Use --fail-on-diff in CI for gating.