=== BEGIN REPAIRED SPECIFICATION ===
# FEATURE: Diagnostics

| Field       | Value |
|-------------|-------|
| Version     | 20260822 V1 |
| Description | Define jq diagnostic, raw stderr, debug, and halt-error behavior. |
| Depends On  | FEATURE-Process-Contract.md, FEATURE-Errors-and-Optional.md |
| Provides    | debug, stderr, halt_error |
| Consumes    | compile and runtime exit contract |

## Scope

Implement `debug`, `stderr`, and `halt_error`, preserving jq's separation of JSON results on stdout from diagnostic and raw output on stderr. `halt_error` must stop evaluation and use its requested exit status while ordinary runtime failures retain exit status 5.

## Programmatic Acceptance

=== AC diagnostics-conformance ===
Intent: The authoritative corpus cases covering jq diagnostics and stderr filters execute successfully.
Suite: scoped
Requires: executable=python3; scope=test

import json
import os
import subprocess
import sys

select = r"debug|stderr|halt_error"
result = subprocess.run(
    [sys.executable, "sources/run_conformance.py", "--select", select, "--json"],
    capture_output=True,
    text=True,
    env={**os.environ, "JQ": f"{os.getcwd()}/jq"},
)
print(result.stdout)
print(result.stderr, file=sys.stderr)
report = json.loads(result.stdout)
summary = report["summary"]
assert sum(summary.values()) > 0
assert summary["fail"] == 0 and summary["error"] == 0
assert result.returncode == 0
=== END AC diagnostics-conformance ===
Intent: The authoritative corpus verifies stdout preservation, stderr side effects, and halt behavior.
Suite: scoped
Requires: executable=python3; scope=test

import json
import os
import subprocess
import sys

select = r"debug|stderr|halt_error"
result = subprocess.run(
    [sys.executable, "sources/run_conformance.py", "--select", select, "--json"],
    capture_output=True,
    text=True,
    env={**os.environ, "JQ": f"{os.getcwd()}/jq"},
)
print(result.stdout)
print(result.stderr, file=sys.stderr)
report = json.loads(result.stdout)
summary = report["summary"]
assert summary["pass"] > 0
assert summary["fail"] == 0
assert summary["error"] == 0
assert result.returncode == 0
=== END AC diagnostics-streams ===

## User Acceptance

- None.

## Guardrails

- Diagnostics must never be emitted on stdout.
- Preserve values emitted before a runtime or halt error.
- Do not compare or depend on diagnostic message text outside the authoritative corpus.
=== END REPAIRED SPECIFICATION ===