feat(litellm): add team name and user name support to LiteLLM credential

[raghava3107]

Summary

Adds a Custom Headers field to the LiteLLM credential, enabling users to pass any LiteLLM proxy headers in API requests. Also adds a comprehensive test suite for the ChatLiteLLM node.

Why is this needed?

LiteLLM is an AI gateway/proxy that routes requests to 100+ LLM providers (OpenAI, Anthropic, Bedrock, etc.) through a unified API. Organizations use LiteLLM for:

• Cost tracking — track spend per team, customer, or environment
• Tag-based routing — route requests to specific model deployments based on tags
• Rate limiting — enforce per-team or per-customer rate limits
• Audit logging — track who made each request

LiteLLM supports several request headers for these features (docs):

Header	Purpose
x-litellm-tags	Tag-based routing and spend tracking (comma-separated)
x-litellm-customer-id	End-user/customer tracking
x-litellm-end-user-id	End-user identification
x-litellm-spend-logs-metadata	Custom metadata in spend logs (JSON string)

Currently, Flowise's LiteLLM integration only supports an API key — there's no way to pass these headers to the proxy.

Solution

Credential (LitellmApi.credential.ts):

• Added optional Custom Headers field (JSON string)
• Example: {"x-litellm-tags": "team:activation,env:prod"}

Chat model (ChatLitellm.ts):

• Parses the custom headers JSON from credential
• Passes them as defaultHeaders in the OpenAI-compatible client configuration
• Malformed JSON is silently ignored (no crash)

Tests (ChatLitellm.test.ts) — 6 tests:

• ✅ Basic initialization with API key and model
• ✅ Custom headers passed correctly to the client
• ✅ Malformed JSON headers handled gracefully
• ✅ Backward compatibility without headers
• ✅ Works without basePath or custom headers
• ✅ Optional parameters (maxTokens, topP, timeout)

Backward Compatibility

The Custom Headers field is optional. Existing LiteLLM configurations continue to work without any changes.

Files Changed

File	Change
packages/components/credentials/LitellmApi.credential.ts	Added litellmCustomHeaders field
packages/components/nodes/chatmodels/ChatLitellm/ChatLitellm.ts	Parse and pass custom headers
packages/components/nodes/chatmodels/ChatLitellm/ChatLitellm.test.ts	New — 6 unit tests

Test Results

PASS nodes/chatmodels/ChatLitellm/ChatLitellm.test.ts
  ChatLitellm
    ✓ initializes with basic config (API key and model only)
    ✓ passes custom headers from credential when provided
    ✓ ignores malformed custom headers JSON gracefully
    ✓ works without custom headers (backward compatible)
    ✓ works without basePath or custom headers
    ✓ passes optional parameters when provided

Test Suites: 1 passed, 1 total
Tests:       6 passed, 6 total

[gemini-code-assist]

Code Review

This pull request introduces optional 'Team Name' and 'User Name' fields to the LiteLLM API credentials. These fields are then extracted and passed as custom headers ('x-litellm-team' and 'x-litellm-user') in the configuration of the ChatLiteLLM model. No review comments were provided, and there is no feedback to address.

Important

The consumer version of Gemini Code Assist on GitHub is being sunset. Starting June 18, 2026, new organization installations will be blocked, and all code review activity will officially cease on July 17, 2026.
For more details on the timeline and next steps, please review the Help Documentation.

[raghava3107]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces support for custom headers in the LiteLLM chat model integration. It adds a new litellmCustomHeaders field to the LiteLLM credentials, parses this field in the model initialization, and forwards the headers to the underlying ChatOpenAI client. Comprehensive unit tests have also been added to cover various scenarios, including malformed JSON handling. The reviewer recommended making the custom headers parsing more robust by checking if the input is already an object before attempting to parse it as a string, preventing potential silent failures.

Important

The consumer version of Gemini Code Assist on GitHub is being sunset. Starting June 18, 2026, new organization installations will be blocked, and all code review activity will officially cease on July 17, 2026.
For more details on the timeline and next steps, please review the Help Documentation.

[gemini-code-assist]

If customHeadersRaw is already parsed or passed as an object (for example, when overridden via API/workflows or if the credential field is populated as an object), calling JSON.parse on it will throw an error and cause the headers to be silently ignored. To make this robust, we should check if customHeadersRaw is already an object before attempting to parse it as a string.

        let defaultHeaders: ICommonObject = {}
        if (customHeadersRaw) {
            if (typeof customHeadersRaw === 'object' && !Array.isArray(customHeadersRaw)) {
                defaultHeaders = customHeadersRaw
            } else if (typeof customHeadersRaw === 'string') {
                try {
                    const parsed = JSON.parse(customHeadersRaw)
                    if (parsed && typeof parsed === 'object' && !Array.isArray(parsed)) {
                        defaultHeaders = parsed
                    }
                } catch {
                    // ignore malformed JSON
                }
            }
        }