Contract Integrity

Contract integrity means every public or release-relevant use of the word

contract is a checked guarantee, not a promise about future work.

For beginners, read a contract as a guarantee with proof. A checked boundary is

the line where 0x0 proves that guarantee through source, tests, diagnostics,

documentation, release evidence, and an owner. If a page does not need that

formal meaning, it should use a simpler word such as guarantee, schema,

policy, profile, or boundary.

Formal Meaning

The formal taxonomy is docs/contract-taxonomy.tsv. A production contract must

be one of these kinds:

• abi-contract;
• api-contract;
• package-contract;
• runtime-contract;
• source-contract;
• tooling-contract;
• test-fixture-contract, for test-only fixtures.

Every non-test contract must point to:

• implementation;
• valid examples;
• invalid examples or negative tests;
• stable diagnostics or failure behavior;
• documentation;
• release evidence;
• compatibility or versioning policy;
• maintenance owner.

Test fixture contracts are allowed only under test-scoped paths and cannot be

used as production evidence.

Evidence Files

The repository-wide evidence is:

• docs/contract-taxonomy.tsv;
• release/contract-inventory.tsv;
• release/contract-rename-ledger.tsv;
• release/contract-integrity-artifacts.tsv;
• release/contract-integrity-closure.tsv;
• release/contract-compatibility.tsv;
• tools/contract-inventory-generate.py;
• tools/contract-integrity-check.py;
• tests/contract-integrity.sh.

Specialized evidence is owned by the surface being proved:

• ABI: abi/contract-inventory.tsv and

release/abi-contract-evidence.tsv;

• API: api/contract-inventory.tsv and

release/api-contract-evidence.tsv;

• package: package/contract-inventory.tsv and

release/package-contract-evidence.tsv;

• runtime: runtime/contract-inventory.tsv and

release/runtime-contract-evidence.tsv;

• source and tooling: source/contract-inventory.tsv,

tooling/contract-inventory.tsv, and

release/source-tooling-contract-evidence.tsv;

• library naming: release/library-contract-name-inventory.tsv,

release/library-contract-rename-ledger.tsv,

libs/symbol-aliases.tsv, and libs/symbol-deprecations.tsv.

Gate

Run the bounded gate:

make contract-integrity-check

The gate validates taxonomy kinds, inventory rows, ownership, fixture scope,

generated inventory drift, rename ledger coverage, release artifact reports,

compatibility notes, and staged ADR/RFC plus documentation-impact requirements

for new contract terminology.

It does not run heavy compiler builds, self-hosting, release packaging, remote

deployment, external services, or hardware probes.

Writing Rule

Use contract in reference documentation only when the page links to

docs/contract-taxonomy.tsv or to this page. In beginner documentation, explain

the guarantee first, then introduce contract only when the formal term helps.

Do not use contract for:

• a roadmap item;
• an idea without implementation;
• an interface-only library;
• a pure constructor that implies runtime behavior;
• a test fixture presented as production behavior;
• a domain value that should be named schema, policy, profile,

descriptor, layout, or boundary.

Related References

• docs/documentation.html: documentation terminology rules.
• docs/governance-review.html: reviewer rules for contract terminology.
• docs/library-contract-naming.html: library source naming cleanup.
• docs/contract-production-roadmap.html: production closure plan.
• docs/release-compat.html: upgrade, downgrade, and compatibility policy.
• docs/final-release-discipline.html: final release decision input.