elsa-workflows/elsa-core · error · ArgumentException

A conversation user ID is required. (Parameter…

Error message

A conversation user ID is required. (Parameter 'conversation')

What it means

InMemoryAIConversationStore.Validate requires every conversation passed to SaveAsync to have a non-whitespace UserId. The user ID is used for ownership checks, so an ArgumentException naming the 'conversation' parameter is thrown when it is missing.

Solutions

1. Set conversation.UserId to the owning user's ID before saving.
2. Ensure user-context resolution populates UserId before store calls.
3. Validate the mapped object before invoking the store.

Example fix

// before
await store.SaveAsync(new AIConversation { Id = id });
// after
await store.SaveAsync(new AIConversation { Id = id, UserId = currentUserId });

if (string.IsNullOrWhiteSpace(conversation.UserId)) throw new ArgumentException("Conversation UserId required");

bool HasUser(AIConversation c) => !string.IsNullOrWhiteSpace(c.UserId);

try { await store.SaveAsync(conversation); } catch (ArgumentException ex) when (ex.ParamName == "conversation") { logger.LogError(ex, "Conversation missing UserId"); }

When it happens

Trigger: Calling SaveAsync with an AIConversation whose UserId is null, empty, or whitespace.

Common situations: Tests constructing conversations without setting UserId; losing the current-user context so UserId defaults to null; deserializing conversations from payloads that omit the user field.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

• A conversation ID is required. (Parameter 'conversation')
• Invalid value type.
• Cannot overwrite an AI conversation that belongs to another…
• Cannot overwrite an AI conversation that belongs to another…
• A conversation ID is required. (Parameter 'conversation')

AI-assisted analysis of elsa-workflows/elsa-core@fe9217bdfa (2026-09-13). Data as JSON: /api/errors/7752b5265caa0b6b. Report an issue: GitHub.

Appendix: source

Thrown at src/modules/Elsa.AI.Host/Services/InMemoryAIConversationStore.cs:74

    private static void ValidateOwnership(AIConversation existing, AIConversation conversation)
    {
        if (!string.Equals(NormalizeTenantId(existing.TenantId), NormalizeTenantId(conversation.TenantId), StringComparison.Ordinal))
            throw new InvalidOperationException("Cannot overwrite an AI conversation that belongs to another tenant.");

        if (!string.IsNullOrWhiteSpace(existing.UserId) && !string.Equals(existing.UserId, conversation.UserId, StringComparison.Ordinal))
            throw new InvalidOperationException("Cannot overwrite an AI conversation that belongs to another user.");
    }

    private static string NormalizeTenantId(string? tenantId) => tenantId ?? "";

    private static void Validate(AIConversation conversation)
    {
        if (string.IsNullOrWhiteSpace(conversation.Id))
            throw new ArgumentException("A conversation ID is required.", nameof(conversation));

        if (string.IsNullOrWhiteSpace(conversation.UserId))
            throw new ArgumentException("A conversation user ID is required.", nameof(conversation));
    }
}

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