rohitg00/ai-engineering-from-scratch · error · ValueError

runtime discovery failed

Error message

runtime discovery failed

What it means

Error "runtime discovery failed" thrown in rohitg00/ai-engineering-from-scratch.

Source

Thrown at phases/19-capstone-projects/13-mcp-server-with-registry/code/main.py:431

        issues.append("runtime serverInfo.version does not match server.json version")
    return issues


@dataclass
class Registry:
    publisher_domain: str = PUBLISHER_DOMAIN
    entries: dict[str, dict] = field(default_factory=dict)
    runtime_discovery: dict[str, dict] = field(default_factory=dict)

    def register(self, server: MCPServer) -> None:
        document = server.registry_document()
        issues = validate_registry_document(document)
        issues.extend(validate_publisher_namespace(document, self.publisher_domain))
        if issues:
            raise ValueError("; ".join(issues))
        discovery = server.discover(request_meta())
        if "error" in discovery:
            raise ValueError("runtime discovery failed")
        alignment_issues = validate_runtime_alignment(document, discovery)
        if alignment_issues:
            raise ValueError("; ".join(alignment_issues))
        self.entries[server.name] = deepcopy(document)
        self.runtime_discovery[server.name] = deepcopy(discovery)

    def search(self, query: str) -> list[str]:
        needle = query.casefold()
        return sorted(
            name
            for name, entry in self.entries.items()
            if needle in name.casefold()
            or needle in entry["title"].casefold()
            or needle in entry["description"].casefold()
        )


def build_readonly_server() -> MCPServer:

View on GitHub (pinned to 39ea8a1c6d)

When it happens

Trigger: Thrown at phases/19-capstone-projects/13-mcp-server-with-registry/code/main.py:431 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of rohitg00/ai-engineering-from-scratch@39ea8a1c6d (2026-08-26). Data as JSON: /api/errors/5e21a505ac3439fc. Report an issue: GitHub.