Harness Specification v0alpha1

The source format is YAML 1.2. The Rust scaffold uses noyalib as the parser and immediately deserializes into typed structs. Unknown-field rejection is a future compatibility decision; the current alpha favors explicit schema evolution over clever extension semantics.

Minimal manifest

apiVersion: prismoid.dev/v0alpha1
kind: Harness
metadata:
  name: hello-prime
  version: 0.1.0

contexts:
  - workspace.directory
capabilities:
  - fs.write_text
policies: []
verifiers:
  - math.prime_file

protocol:
  instructions:
    - Produce a durable artifact.

limits:
  max_steps: 8

Fields

`apiVersion`

Must be prismoid.dev/v0alpha1 for this scaffold.

`kind`

Must be Harness.

`metadata`

name: stable package-local name.
version: semantic version string. Package resolution is not implemented yet.

`contexts`

Names of ContextProvider ports that the application/environment must bind before execution.

`capabilities`

Names of capabilities the model may propose. The runtime refuses unbound or undeclared capabilities.

`policies`

Policies evaluated for every proposed action. The most restrictive result wins.

`verifiers`

Required verifiers. At least one verifier is mandatory. Completion requires every verifier to return pass; fail becomes feedback for another inference step while budget remains. uncertain and requires_human stop automatic completion.

`protocol.instructions`

Ordered method guidance passed to the model. Protocol composition will become a compiler concern; it is intentionally not a workflow graph in v0alpha1.

`limits.max_steps`

Maximum model turns. It is a safety boundary, not merely a cost setting.

Future compilation pipeline

source manifests
    -> package resolution
    -> inheritance/composition
    -> conflict checking
    -> capability requirement solving
    -> policy lattice merge
    -> verifier union
    -> protocol composition
    -> normalized Harness IR
    -> lockfile + digest

The runtime must never own these source-level merge rules.