HKUDS/Vibe-Trading · error · ValueError

manifest file {manifest_path} is not valid JSON: {exc.msg} a

Error message

manifest file {manifest_path} is not valid JSON: {exc.msg} at line {exc.lineno} column {exc.colno}

What it means

load_manifest parses the manifest bytes as JSON with json.loads; a JSONDecodeError (syntax error such as trailing commas, single quotes, comments, truncated file) is re-raised as ValueError including the parser message plus line/column of the fault. The file was readable but not valid JSON.

Source

Thrown at agent/src/tools/strategy_discovery_tool.py:474

            f"manifest path {manifest_path} could not be resolved: {exc}"
        ) from exc
    if not _manifest_path_allowed(resolved_manifest):
        raise ValueError(
            f"manifest path {manifest_path} is outside the runtime root and "
            "the allowed run roots; place the manifest under one of them "
            "(e.g. next to the runs it lists)"
        )
    try:
        raw = manifest_path.read_text(encoding="utf-8")
    except OSError as exc:
        raise ValueError(
            f"manifest file {manifest_path} is missing or unreadable "
            f"({exc.strerror or 'I/O error'})"
        ) from exc
    try:
        parsed = json.loads(raw)
    except json.JSONDecodeError as exc:
        raise ValueError(
            f"manifest file {manifest_path} is not valid JSON: {exc.msg} "
            f"at line {exc.lineno} column {exc.colno}"
        ) from exc
    if isinstance(parsed, list):
        return parsed
    if isinstance(parsed, dict):
        runs = parsed.get("runs")
        if not isinstance(runs, list):
            raise ValueError(
                f"manifest file {manifest_path} must be a JSON object with a "
                "'runs' array or a bare JSON array of run specs"
            )
        return runs
    raise ValueError(
        f"manifest file {manifest_path} must be a JSON object with a 'runs' "
        "array or a bare JSON array of run specs"
    )

View on GitHub (pinned to 80ffdda44c)

Solutions

1. Validate the file: python -m json.tool <path> to see the exact syntax error position
2. Remove comments/trailing commas, use double quotes, null/false/true literals
3. Regenerate the manifest programmatically with json.dump instead of editing by hand

Example fix

# before (manifest.json)
{ "runs": [ {"id": "r1",}, ] }
# after
{ "runs": [ {"id": "r1"} ] }

import json
json.loads(Path(manifest_path).read_text(encoding="utf-8"))  # fail fast with line/col

except ValueError as e: surface the line/column from the message to pinpoint the JSON syntax error

When it happens

Trigger: Manifest containing trailing commas, unquoted keys, Python-style None/True literals, single-quoted strings, or a truncated file; e.g. a hand-edited manifest with a comment line // runs.

Common situations: Hand-editing manifests in an editor that allows JSON5-style syntax; concatenating JSON files without joining into an array; log truncation cutting the last entry; YAML mistakenly saved with a .json extension.

Related errors

• manifest path {manifest_path} could not be resolved: {exc}
• manifest path {manifest_path} is outside the runtime root an
• manifest file {manifest_path} is missing or unreadable ({exc
• manifest file {manifest_path} must be a JSON object with a '
• run_id must not be empty

AI-assisted analysis of HKUDS/Vibe-Trading@80ffdda44c (2026-08-28). Data as JSON: /api/errors/f71dbcb6f9043698. Report an issue: GitHub.