[Bug]: Context engine context_chunking not found during first auxiliary agent initialization despite plugin being available

[abdalawood]

Bug Description

Environment

• Hermes Agent v0.18.2 (2026.7.7.2)
• Docker installation
• OpenAI Codex provider
• Context engine: context_chunking

Problem

The logs show:

Context engine 'context_chunking' not found — falling back to built-in compressor

However:

• context.engine is set to context_chunking

• plugin is enabled

• plugin exists in:

  /opt/data/plugins/context_chunking/

• plugin discovery reports:

  plugin_context_engine =
  ('context_chunking',
  'hermes_plugins.context_chunking',
  'ContextChunkingEngine')

The native directory:

/opt/hermes/plugins/context_engine/context_chunking/

does not exist.

Observations

• The first direct loader fails.
• The general plugin fallback successfully finds ContextChunkingEngine.
• After creating a new auxiliary agent, the warning no longer appears.
• The system works correctly despite the warning.

Expected

If the plugin fallback succeeds, the warning should not be emitted.

Steps to Reproduce

1. Configure:

context:
engine: context_chunking

plugins:
enabled:
- context_chunking

2. Ensure the plugin exists under:

/opt/data/plugins/context_chunking/

3. Start Hermes.

4. Trigger creation of an auxiliary agent (for example during automatic context compression or when a new helper agent is spawned).

5. Observe the logs.

Expected Behavior

When context.engine is configured as "context_chunking" and the plugin is enabled and successfully discovered by the plugin system, Hermes should load the ContextChunkingEngine without emitting any warning.

If the plugin fallback succeeds, no "Context engine not found" warning should be logged.

Actual Behavior

Hermes logs:

Context engine 'context_chunking' not found — falling back to built-in compressor

However, the plugin is actually present and discoverable through the general plugin system.

Plugin discovery reports:

plugin_context_engine =
('context_chunking',
'hermes_plugins.context_chunking',
'ContextChunkingEngine')

After initialization, the plugin works correctly and the warning may no longer appear.

Affected Component

Agent Core (conversation loop, context compression, memory)

Messaging Platform (if gateway-related)

Telegram

Debug Report

Output of:

hermes debug share --local

was too large for the GitHub issue form (>65k characters).

Attached separately / available on request.

Relevant environment:

Hermes 0.18.2
Python 3.11.15
WSL2
Docker
Provider: openai-codex (gpt-5.5)

Operating System

WSL2 Ubuntu 24.04

Python Version

3.11.15

Hermes Version

Hermes Agent v0.18.2 (2026.7.7.2)

Additional Logs / Traceback (optional)

WARNING run_agent: Context engine 'context_chunking' not found — falling back to built-in compressor

Root Cause Analysis (optional)

The plugin is not available as a built-in context engine under:

/opt/hermes/plugins/context_engine/context_chunking/

However, it is installed as a user plugin under:

/opt/data/plugins/context_chunking/

The direct context engine loader fails, but the general plugin registry successfully discovers:

ContextChunkingEngine

This suggests a possible initialization-order issue or inconsistency between the direct context engine loader and the plugin fallback during auxiliary agent creation.

Proposed Fix (optional)

If the general plugin registry successfully resolves the requested context engine, Hermes should not emit:

Context engine 'context_chunking' not found

The warning should only be logged if both the native loader and the plugin fallback fail.

Alternatively, ensure that plugin registration is completed before auxiliary agents attempt to resolve the configured context engine.

Are you willing to submit a PR for this?

• I'd like to fix this myself and submit a PR

[abdalawood]

Additional investigation

While debugging this issue I found the following:

• context.engine is configured as context_chunking.
• The agent tries to load it through:

load_context_engine("context_chunking")

(from agent/agent_init.py).

However, the native context engine directory does not exist:

/opt/hermes/plugins/context_engine/context_chunking/

The plugin actually exists as a user plugin:

/opt/data/plugins/context_chunking/

Plugin discovery reports:

plugin_context_engine =
('context_chunking',
 'hermes_plugins.context_chunking',
 'ContextChunkingEngine')

and the plugin is enabled.

Despite that, the agent still logs:

WARNING run_agent:
Context engine 'context_chunking' not found — falling back to built-in compressor

This suggests that:

• the native context-engine loader cannot find the engine;
• the standalone plugin is discovered correctly;
• somewhere between the loader and the fallback, the plugin is still not being attached to the agent.

The issue does not appear to be caused by the user configuration, since:

context:
  engine: context_chunking

plugins:
  enabled:
    - context_chunking

is correctly loaded inside the container.

This looks like either:

a regression in the context-engine loading sequence, or
the standalone context engine plugin is no longer compatible with the current loader.

[GottZ]

This was generated by AI during triage.

Summary

Two PRs address #61839's order-dependent context-engine discovery failure. #61995 performs a PluginManager-owned, configuration-gated one-time refresh and adds regression coverage, while #62465 retries from agent initialization by globally forcing plugin rediscovery.

Related pull requests

• fix(agent): load user-installed context engines without false not-found warning (#61839) #61995 best fix — (+175/-1) — fixes: The current diff resolves the stale-manager path inside PluginManager, preserves enabled/disabled gates, avoids replaying registration, and verifies first-initialization recovery, single execution, and disabled-plugin behavior. Despite the earlier keep_open review on fix(agent): load user-installed context engines without false not-found warning (#61839) #61995, the revised diff directly addresses its blocking concerns by removing direct imports, repeated register() calls, and alias matching.
• fix(agent): force plugin re-discovery when context engine not found on first try #62465 [closed] partial — (+14/-2) — partial fix: It retries after a failed lookup, but discover_plugins(force=True) resets all plugin registries from agent initialization and the diff adds no regression test for the reported ordering failure. Although its review said keep_open, the contributor follow-up marks it stale because the requested targeted resolution was not implemented; the closed PR remains relevant as the broader, higher-risk retry approach superseded by fix(agent): load user-installed context engines without false not-found warning (#61839) #61995.

Duplicates

#61995 and #62465 target the same stale-discovery failure, but they are not patch-equivalent; #62465's global forced rediscovery is superseded by #61995's targeted, gated one-time refresh.

Suggested consolidation

Merge #61995 as the canonical fix: its revised diff addresses the contributor review objections and includes focused regression coverage for the reported first-initialization path. Keep #62465 closed as superseded by #61995 rather than reopening it over the unresolved blocking review.

Complex graph

flowchart LR
    classDef open fill:#dbeafe,stroke:#1d4ed8,color:#1e3a8a
    classDef merged fill:#dcfce7,stroke:#15803d,color:#14532d
    classDef closed fill:#e5e7eb,stroke:#6b7280,color:#1f2937
    classDef unverified fill:#f3f4f6,stroke:#9ca3af,color:#374151
    classDef best stroke-width:3px,stroke:#b45309
    classDef target stroke-width:3px,stroke:#4338ca
    I61839(["issue #61839 (open)"])
    P61995["PR #61995 (open)"]
    P62465["PR #62465 (closed)"]
    P61995 -->|best fix| I61839
    P62465 -.->|partial| I61839
    class I61839 open
    class I61839 target
    class P61995 open
    class P62465 closed
    class P61995 best
    click I61839 "https://github.com/NousResearch/hermes-agent/issues/61839"
    click P61995 "https://github.com/NousResearch/hermes-agent/pull/61995"
    click P62465 "https://github.com/NousResearch/hermes-agent/pull/62465"

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Graph: solid arrow = fixes / best fix, dashed arrow = partial or unverified (see edge label); boxed group = PRs duplicating each other; amber border = best fix; indigo border = target; gray node = closed or no verify verdict yet (state tag in the node label).

Cross-PR triage: Reviewed 2 pull requests and 1 issue in this complex. Each diff was read against this issue; Assessment working set: 9 kB of PR diffs, 8 kB of issue/PR text, 6 kB of discussion (7 comments), 3 verify verdicts. verdicts reflect diff content, not PR titles. Part of an automated triage batch.