BRIK64 PCD 1.0 Protocol

Public repository for the BRIK64 PCD 1.0 protocol: what a PCD is, how it is created, how it is packaged, and how agents and developers should treat it.

Status: v1.0 implementation baseline

Source authority for this publication:

• brik64-prod commit cb516bd554399ba784ef1b7da36a9f3e28773ad1
• docs/standards/PCD_FILE_STANDARD_V1.md
• docs/standards/PCD_PROGRAMMING_STANDARD_V1.md
• docs/standards/BRIK64_STANDARDS_INDEX.md
• software/spec/pcd_file.schema.json
• software/spec/pcd_file_metadata.schema.json

What PCD Is

PCD means Program Circuit Description in the public BRIK64 protocol. A PCD is a software-logic circuit description: a bounded statement of inputs, outputs, operations, composition and traceability metadata.

PCD is not a general scripting language. It is not a marketing label. It is the format BRIK64 uses to make software logic inspectable before it is connected to evidence workflows.

At minimum, a PCD records:

• the circuit boundary;
• the expected inputs;
• the produced output;
• the monomer or operation vocabulary used;
• the composition structure;
• the exact source bytes to hash;
• metadata and evidence references that are non-semantic.

What Digital Circuitality Is

Digital Circuitality is the BRIK64 methodology for turning software logic into bounded, composable, traceable units. It asks agents and developers to treat software like circuit design:

• define the boundary before writing logic;
• keep operations explicit;
• make composition visible;
• preserve traceability;
• separate examples and metadata from evidence claims.

PCD is the public file/source protocol for expressing that discipline.

What BRIK64 Is

BRIK64 is the ecosystem around PCD, .brik workspaces, the public CLI, agent skills, documentation and evidence workflows. This repository defines the PCD protocol layer. It does not replace the CLI, docs site, .brik workspace standard, or evidence packs.

PCD 1.0 Layers

The public standard is split into two layers:

• PCD File Standard v1.0: JSON envelope, metadata, canonical hash, and certification-reference container rules.
• PCD Programming Standard v1: compiler-bound source profile for PCD files that are intended to feed the active BRIK64 compiler path.

Creation Protocol

To create a PCD 1.0 artifact:

1. State the requirement in plain language.
2. Define inputs and output.
3. Define fail-closed behavior.
4. Select the smallest operation vocabulary that expresses the logic.
5. Describe the composition structure.
6. Write raw .pcd source using the active authoring profile.
7. If distributing or synchronizing, wrap the exact source bytes in the PCD file envelope.
8. Compute semantic_pcd_sha256 over exact pcd_source bytes.
9. Add metadata only as non-semantic context.
10. Add evidence or certification references only as references.
11. Validate with the current BRIK64 tooling before using the artifact in a release, package or public report.

Public Boundary

This repository publishes file and authoring standards. It does not publish a compiler, runtime, certificate, evidence pack, or formal proof. Public claims about a specific BRIK64 artifact must point to the corresponding release, certificate, report, or evidence bundle.

Repository Layout

• docs/BRIK64_STANDARDS_INDEX.md
• docs/PCD_FILE_STANDARD_V1.md
• docs/PCD_PROGRAMMING_STANDARD_V1.md
• schemas/pcd_file.schema.json
• schemas/pcd_file_metadata.schema.json
• SPEC.md
• DIGITAL_CIRCUITALITY.md
• AUTHORING.md
• FORMAT.md
• CLI_INTEGRATION.md
• CLAIM_BOUNDARY.md
• VERSIONING.md
• EXAMPLES.md
• AGENTS.md

Product documentation: https://docs.brik64.com