Flow Builder Assistant doesn't recognize `LANGFLOW_COMPONENTS_PATH` bundle components as custom components — reports them as built-ins or omits them entirely

[kartikgajjar]

Use latest reply, it has updated information

Bug Description

When custom components are installed via LANGFLOW_COMPONENTS_PATH (the documented way to ship a directory of custom component bundles), the Flow Builder Assistant has no way to recognize them as custom/user components:

1. The component registry carries no origin marker. Bundle components appear in search_components results under their folder name as the category (e.g. acme_tools, acme_data) with internal names like ext:<bundle>:<ClassName>@extra (1.10 extension naming). Nothing in the returned fields distinguishes them from built-in bundles like openai or google.

2. The assistant's system prompt only covers session-generated components. The "User-generated components (CRITICAL)" section of langflow/agentic/flows/flow_builder_assistant.py describes components created via generate_component in the current session, but never mentions LANGFLOW_COMPONENTS_PATH bundles. The only category the model can associate with "custom" is custom_component — which contains just the built-in Custom Component placeholder and session-generated components.

Observed Behavior

Instance with 24 custom components installed across 4 bundle folders (LANGFLOW_COMPONENTS_PATH=./custom_components, all loading correctly and usable on the canvas). User asks the assistant:

"list all custom component names, even if they are not part of the current flow"

The assistant calls search_components (no args, full registry — all 24 bundle components are present in the result), then answers:

"These are the only two custom (non-built-in) components available in your registry. All other 280+ components belong to standard Langflow categories."

…listing only one component that happened to be on the canvas and one session-generated component from the custom_component category. The 24 installed bundle components were classified as "standard Langflow categories" and omitted.

Expected Behavior

The assistant should report operator-installed bundle components as custom components. Concretely, either or both of:

• search_components exposes an origin field (e.g. source: "builtin" | "components_path" | "generated"), so the model doesn't have to infer it from category names, and/or
• The Flow Builder system prompt documents that LANGFLOW_COMPONENTS_PATH bundles appear under their folder-name categories with ext:<bundle>:<Class>@extra names and must be treated as custom components.

Steps to Reproduce

1. pip install langflow==1.10.0.
2. Set LANGFLOW_COMPONENTS_PATH to a directory containing one or more bundle folders with valid custom components.
3. Start Langflow, confirm the components appear in the sidebar and the registry (search_components returns them under the folder-name category).
4. Ask the Flow Builder Assistant to "list all custom component names, even if they are not part of the current flow."
5. The assistant reports only the custom_component category and omits every installed bundle component.

Suggested Fix

Minimal (prompt-only): add to the "User-generated components (CRITICAL)" section of flow_builder_assistant.py:

Components installed from the operator's components path (LANGFLOW_COMPONENTS_PATH bundles) are ALSO custom/user components, not built-ins. They appear in search_components under their bundle folder's category (the folder name, not custom_component) with internal names like ext:<bundle>:<ClassName>@extra. When the user asks about their "custom components", include BOTH session-generated components AND every component from these bundle categories — do not report only the custom_component category.

More robust (data): have list_all_components / search_components include an explicit origin/source field for each component so the distinction doesn't rely on prompt knowledge.

Reproduction

1. pip install langflow==1.10.0.
2. Set LANGFLOW_COMPONENTS_PATH to a directory containing one or more bundle folders with valid custom components.
3. Start Langflow, confirm the components appear in the sidebar and the registry (search_components returns them under the folder-name category).
4. Ask the Flow Builder Assistant to "list all custom component names, even if they are not part of the current flow."
5. The assistant reports only the custom_component category and omits every installed bundle component.

Expected behavior

The assistant should report operator-installed bundle components as custom components. Concretely, either or both of:

• search_components exposes an origin field (e.g. source: "builtin" | "components_path" | "generated"), so the model doesn't have to infer it from category names, and/or
• The Flow Builder system prompt documents that LANGFLOW_COMPONENTS_PATH bundles appear under their folder-name categories with ext:<bundle>:<Class>@extra names and must be treated as custom components.

Environment

• Langflow: 1.10.0 (pip install)
• lfx: 1.10.0
• Python: 3.13
• OS: Windows 11
• LANGFLOW_COMPONENTS_PATH=./custom_components with 4 bundle folders / 24 components, all loading and usable on canvas

Who can help?

@Cristhianzl

Same install also hit the component_code_search silent-empty-column defect in the bundled LangflowAssistant flow (filed separately).

Operating System

Windows 11

Langflow Version

1.10.1

Python Version

3.12

Screenshot

flow_builder_assistant.py

Flow File

No response

[kartikgajjar]

Bug Description

The Flow Builder Assistant's discovery and build tools do not use the live component registry. SearchComponentTypes, DescribeComponentType, and BuildFlowFromSpec (lfx/mcp/flow_builder_tools/) load their registry via _load_registry_user_aware(), which resolves to:

1. A static index bundled inside the lfx package — lfx/_assets/component_index.json, loaded by load_local_registry() in lfx/graph/flow_builder/builder.py. It is generated at package build time and contains only built-in components (354 in lfx 1.10.0).
2. A per-user overlay (langflow/agentic/services/user_components_overlay.py) that adds only components generated in-session via generate_component (the user's sandbox .components/*.py files).

Components installed via LANGFLOW_COMPONENTS_PATH — the documented mechanism for deploying custom component bundles — appear in neither source. They load fine into the live registry (get_and_cache_all_types_dict, the sidebar, /api/v1/all, and the separate MCP-server search_components in langflow/agentic/mcp/server.py all see them), but the Flow Builder agent is completely blind to them: it cannot list them, describe them, or use them in build_flow.

The same blindness affects the Support/Q&A assistant (the bundled LangflowAssistant flow). Its component_code_search tool indexes component source files via a Directory node whose path is rewritten at runtime to the installed lfx/components package (inject_lfx_components_path) — built-ins only. The directories configured in the settings' components path are never indexed, so this surface cannot find operator-installed components either.

Net effect: whichever agent a question routes to, the assistant confidently reports that the user's installed components do not exist, since its tool results genuinely lack them.

Observed Behavior

Instance with 24 custom components across 4 bundle folders (LANGFLOW_COMPONENTS_PATH set, all components loading correctly, visible in the sidebar and usable on the canvas). User asks the assistant:

"list only custom components, even if they are not part of the current flow"

The assistant calls search_components (full registry listing) and answers:

"Based on the search results, there is 1 custom component registered: ExcelToJsonComponent ... That's the only component in the custom_component category."

The one component it found is a session-generated component from the per-user overlay. All 24 installed bundle components were absent from the tool result.

Expected Behavior

The Flow Builder Assistant's registry should reflect what is actually installed on the server — at minimum, merge LANGFLOW_COMPONENTS_PATH bundles into the registry the same way the live /api/v1/all endpoint does, so the assistant can discover, describe, and build flows with operator-installed components.

Steps to Reproduce

1. pip install langflow==1.10.0.

2. Set LANGFLOW_COMPONENTS_PATH to a directory containing bundle folders with valid custom components; start Langflow and confirm they appear in the sidebar.

3. Ask the Flow Builder Assistant to list custom components, or to describe / build a flow with one of them by name.

4. The assistant reports they don't exist. Deterministic check without the UI:

   from lfx.graph.flow_builder.builder import load_local_registry
   from lfx.mcp.registry import search_registry
   registry = load_local_registry()           # what the assistant's tools search
   print(search_registry(registry, query="<YourBundleComponent>"))   # -> []

   while langflow.agentic.utils.component_search.list_all_components() (live registry) returns the same component.

Workaround (verified)

Injecting the bundle categories from the live registry (get_and_cache_all_types_dict) into lfx/_assets/component_index.json — same [category, {name: component_data}] entry shape — makes the assistant's exact tool path work: search_registry then returns all bundle components and describe_component produces correct inputs/outputs for them. This confirms the only missing piece is the registry data; no tool/prompt logic changes are required for discovery.

Suggested Fix

• Flow Builder: have _load_registry_user_aware() (or load_registry_with_user_overlay) additionally merge components from the settings' components_path, mirroring get_and_cache_all_types_dict. The static index would then only serve as the built-in base, as today, while operator-installed bundles stay visible to the assistant.
• Support assistant: have inject_lfx_components_path (or the Directory node setup) also include the settings' components_path directories in the source index so component_code_search covers operator-installed component code. Verified locally: pointing the Directory node at a folder containing both built-in and components_path sources makes the assistant's search return the installed components correctly.

Additionally, the Flow Builder system prompt (flow_builder_assistant.py) only describes session-generated components as "custom"; once bundle components are visible, a sentence noting that bundle-category components (ext:<bundle>:<ClassName>@extra under folder-name categories) are also user components would prevent the model from classifying them as built-ins.

Environment

• Langflow: 1.10.0 (pip install)
• lfx: 1.10.0
• Python: 3.13
• OS: Windows 11
• LANGFLOW_COMPONENTS_PATH with 4 bundle folders / 24 components, all loading and usable on canvas

Related

Same install also hit the component_code_search silent-empty-column defect in the bundled LangflowAssistant flow (filed separately).

[AntonioABLima]

Thank you for another excellent report! I have successfully reproduced this issue as well against the current codebase and created an internal ticket for the engineering team. (LE-1523)

Your consistent, high-quality documentation is incredibly helpful and saves us a lot of time.

Thanks again for your continued support and for helping us improve the project!

[kartikgajjar]

@AntonioABLima Thank you !!