openclaw - 💡(How to fix) Fix [Bug]: Message Streaming in Mattermost active even if disabled in config file. Also Bot-to-Bot communication disabled but allowed in config [2 comments, 1 participants]

Bug type

Regression (worked before, now fails)

Beta release blocker

No

Summary

Following the update to version 2026.4.21, we are experiencing a severe regression regarding inter-agent communication and configuration adherence across multiple channels.

Observed Issues:

Complete Agent-to-Agent Isolation: Agents are no longer able to trigger or see messages from other agents across all connected surfaces (e.g., Mattermost, custom WebSockets). While human-to-agent and agent-to-human communication remains functional, all agent-to-agent events are silently dropped or filtered. Configuration Override / Ignored Settings: The Gateway is ignoring explicit configuration flags. Specifically, response streaming is being forced in Mattermost even though it has been explicitly disabled in the config. Inconsistent Event Routing: The breakdown of the agent-to-agent pipeline suggests a fundamental change or bug in the event routing/filtering logic introduced in the latest update. Impact: This completely breaks collaborative workflows and social interactions between multiple agents, effectively isolating them into separate silos despite being in the same channel.

Steps to reproduce

• Setup: Deploy two or more agents (e.g., Agent A and Agent B) into the same channel on any supported surface (e.g., Mattermost or a custom WebSocket implementation).

• Configuration: Ensure that agentToAgent.enabled is set to true in the Gateway configuration.

• Trigger: Use Agent A to send a message that explicitly mentions Agent B (e.g., @AgentB hello).

• Observation: Observe that Agent B does not receive the event and does not respond, despite being active and correctly paired.

• Comparison: Use sessions_send to send a direct internal message from Agent A to Agent B. Observe that this internal communication still works, confirming the issue is isolated to the channel-based event routing.

• Config Check: Set streaming: false in the provider configuration (e.g., for Mattermost) and observe that the Gateway continues to stream responses regardless.

Expected behavior

• Agent-to-Agent Transparency: Agents should be able to perceive and respond to messages from other agents in shared channels, provided that the appropriate permissions (e.g., agentToAgent.enabled=true) are configured. Communication should flow naturally as it did in previous versions.

• Strict Configuration Adherence: The Gateway must respect all explicitly defined configuration flags. If streaming is disabled in the config, the Gateway should deliver responses as blocks, regardless of the platform's capabilities.

• Consistent Event Propagation: Events triggered by one agent should be propagated to all other relevant agent sessions in the same context without being silently filtered out by the routing layer.

Actual behavior

Agent Interaction: When one agent sends a message mentioning another agent in a shared channel (e.g., Mattermost), the targeted agent remains silent and does not trigger any response, despite being active and authenticated.

Cross-Channel Consistency: This behavior is consistently observed across multiple surfaces, including both the Mattermost provider and a custom WebSocket-based frontend (ClawChat).

Internal Communication: In contrast to channel events, direct inter-session communication via the sessions_send tool remains functional, indicating that the failure is specific to the channel-based event propagation layer.

Configuration Failure: The Gateway delivers responses via streaming in Mattermost, directly contradicting the explicit streaming: false setting in the configuration file.

OpenClaw version

2026.6.21

Operating system

macOS 25.4.0 (arm64)

Install method

mac app

Model

ollama/glm-5.1:cloud / ollama/gemma4:31b-cloud

Provider / routing chain

Mattermost -> OpenClaw Gateway -> Agent A -> OpenClaw Gateway -> Agent B -> OpenClaw Gateway -> Mattermost

Additional provider/model setup details

• Provider: Mattermost (Channel-based communication)
• Routing Path: Mattermost - Gateway - Agent A - Gateway - Agent B - Gateway - Mattermost
• Observed Failure Point: The break occurs at the second leg of the chain (Agent A - Gateway - Agent B). The event is sent by Agent A, but the Gateway fails to route/propagate this event to Agent B, despite both agents being active in the same channel.

Logs, screenshots, and evidence

Impact and severity

• Who is affected: All multi-agent setups where two or more agents are deployed in the same channel/surface.

• Severity: High / Critical.

• Frequency: 100% reproduction rate. Every attempt to communicate agent-to-agent via standard channel events fails.

• Practical Consequences:

• Complete loss of inter-agent collaboration and coordination.

• Agents are isolated into individual silos, making collaborative tasks or synchronized responses impossible.

• Configuration settings (e.g., disabling streaming) are being ignored by the Gateway, leading to unexpected UI behavior (forced streaming in Mattermost).

• Observed Evidence:

• Direct mentions (@mention) from one agent to another in Mattermost and ClawChat do not trigger responses from the targeted agent.

• Internal sessions_send calls still work, confirming that the agents are active, but the Gateway-level event routing for channels is broken.

• Forced streaming in Mattermost despite streaming: false in the configuration.

Additional information

No response