langchain-ai/deepagents · error · MarketplaceError

Could not read marketplace manifest {manifest_path}: {exc}

Error message

Could not read marketplace manifest {manifest_path}: {exc}

What it means

When reading a marketplace manifest from disk, an OSError (permission denied, missing file, I/O error) is caught and re-raised as MarketplaceError with the path and OS detail. This distinguishes 'could not read the file at all' from 'file read but bad JSON'.

Source

Thrown at libs/code/deepagents_code/plugins/marketplace.py:811

        name=name,
        source=source,
        description=description_value if isinstance(description_value, str) else None,
        author=author,
        display_name=(
            display_name_value if isinstance(display_name_value, str) else None
        ),
    )


def _load_marketplace_from_path(root: Path, manifest_path: Path) -> PluginMarketplace:
    try:
        raw = json.loads(manifest_path.read_text(encoding="utf-8"))
    except json.JSONDecodeError as exc:
        msg = f"Invalid JSON syntax in {manifest_path}: {exc}"
        raise MarketplaceError(msg) from exc
    except OSError as exc:
        msg = f"Could not read marketplace manifest {manifest_path}: {exc}"
        raise MarketplaceError(msg) from exc
    if not isinstance(raw, dict):
        msg = f"Marketplace manifest {manifest_path} must be a JSON object"
        raise MarketplaceError(msg)
    try:
        name = _validate_name(raw.get("name"), allow_at=False)
    except ValueError as exc:
        raise MarketplaceError(str(exc)) from exc
    plugins_raw = raw.get("plugins")
    if not isinstance(plugins_raw, list):
        msg = f"Marketplace {name} must contain a plugins array"
        raise MarketplaceError(msg)
    warnings: list[str] = []
    plugins = tuple(
        plugin
        for entry in plugins_raw
        if (plugin := _parse_entry(entry, warnings=warnings)) is not None
    )
    for warning in warnings:

View on GitHub (pinned to a1af029e6e)

Solutions

1. Check the file exists and is readable: `ls -l <path>` and `cat <path>`; fix permissions with chmod/chown.
2. Repair or recreate the broken symlink pointing at the manifest.
3. If on a network mount, restore the mount and retry loading the marketplace.

Example fix

// before: unreadable file
$ chmod 600 ~/.marketplaces/team/.marketplace.json
// after
$ chmod 644 ~/.marketplaces/team/.marketplace.json

from pathlib import Path

def manifest_readable(path: Path) -> bool:
    return path.is_file() and os.access(path, os.R_OK)

def is_readable_file(p: object) -> TypeGuard[Path]:
    return isinstance(p, Path) and p.is_file() and os.access(p, os.R_OK)

try:
    mp = load_marketplace(root)
except MarketplaceError as exc:
    if "Could not read" in str(exc):
        fix_permissions_or_restore(exc)
    raise

When it happens

Trigger: load_marketplace(root) (or _load_marketplace_file / add_local_marketplace) reaching _load_marketplace_from_path where manifest_path.read_text() raises OSError — e.g. path deleted between discovery and read, no read permission, or a broken symlink.

Common situations: Manifest found by find_marketplace_manifest via a symlink whose target was removed; file locked or unreadable under a different user; disk/network mount unavailable; SELinux/AppArmor denying read.

Related errors

• could not update {DEFAULT_CONFIG_PATH}
• {target}: {exc}
• debug log directory is not owned by the current user: {path}
• Cannot determine whether {str(left)!r} is {str(right)!r}: {e
• Invalid DEEPAGENTS_HOME {str(root)!r}: exists but cannot be

AI-assisted analysis of langchain-ai/deepagents@a1af029e6e (2026-08-29). Data as JSON: /api/errors/58d819a3adec6701. Report an issue: GitHub.