- Added a reconnection retry mechanism for MCP tool calls and tool listing operations to handle stale connections.
- Enhanced error logging to provide clearer feedback during reconnection attempts.
- Updated comments for clarity on the retry behavior and connection management.
When an MCP tool returns image content items, the agent engine now
automatically generates text descriptions using the configured VLM
model and appends them to the tool result message. This makes image
content accessible to LLMs that receive tool results as text.
Images are not passed directly to the LLM because Chat Completions API
does not reliably support images in tool role messages across providers
(tested: gpt-5.4 silently ignores them, Qwen3.5 processes them).
Changes:
- Add Images field to ToolResult for preserving base64 data URIs
- Add extractContentAndImages() with MIME whitelist, size/count limits
- Add ImageDescriberFunc injection to AgentEngine (no vlm package dep)
- Add describeImages() with graceful error handling and ctx cancellation
- Add VLM model injection in CreateAgentEngine (same pattern as
SetAppConfig/SetSkillsManager)
- Redact image base64 from Data map to prevent log/SSE exposure
- Use service.Name instead of service.ID (UUID) for stable tool names
across MCP server reconnections
- Add (tenant_id, name) unique index on MCPService to prevent name
collisions at the DB level
- Add collision detection logging in RegisterMCPTools for defense-in-depth
- Improve truncation logic to prioritize keeping the tool name intact
Security: first-wins policy in ToolRegistry + unique name constraint
prevents tool hijacking (GHSA-67q9-58vj-32qx).
When an MCP server re-registers after long idle, a new UUID is generated,
causing tool names to change and agent tool calls to fail. Switch from
t.service.ID to t.service.Name so tool names remain stable across
re-registrations.
- Introduced a constant `maxFunctionNameLength` set to 64 characters to comply with OpenAI API constraints on tool names.
- Updated the `Name` method in `MCPTool` to truncate tool names exceeding the maximum length, ensuring unique identification while preventing potential collisions.
- Enhanced the logic to handle long service IDs by using only the first 8 characters when necessary, maintaining the integrity of tool naming conventions.
These changes improve compliance with API requirements and enhance the robustness of tool name generation.
- Updated the tool name format to use service ID instead of service name, preventing name collisions across MCP services.
- Modified the tool description to indicate external sources, reducing the risk of indirect prompt injection.
- Added a prefix to the MCP tool output to treat it as untrusted data, further mitigating security risks.
- Added duration tracking for agent steps and tool calls, improving event data accuracy.
- Updated AgentStreamDisplay and ToolResultRenderer components to include fallback headers and improved output styling.
- Refactored duration handling in the agent engine and session management to ensure consistent duration reporting.
- Enhanced UI elements for better user experience, including scrollable output areas and improved tooltip visibility.
- Added support for stdio transport type in MCP service configuration, allowing command execution via standard input/output.
- Updated MCPService interface to include optional stdio_config and env_vars fields for managing command arguments and environment variables.
- Enhanced frontend components to handle stdio transport, including dynamic form fields for command and arguments.
- Implemented validation logic for stdio configuration in the service update process, ensuring proper handling of required fields.
- Updated backend logic to manage stdio transport connections and ensure proper client lifecycle management.
- Updated RegisterMCPTools and GetMCPToolsInfo functions to accept a context parameter, improving control over timeouts and cancellations.
- Implemented timeout handling for ListTools operations to prevent hanging during long-running requests.
- Enhanced GetFunctionDefinitions to include all MCP tools regardless of the allowed tools list, ensuring comprehensive tool access.
- Improved MCP service management by adding checks for service enabled state and critical configuration changes, ensuring robust client connection handling.
- Refactored session handling to utilize AgentModeEnabled for better session configuration management.
- Introduced new MCP services functionality, including management routes and integration with the agent service.
- Updated Docker Compose configuration to include a new SQL migration for MCP services.
- Enhanced Makefile with new migration commands for versioning and creating migrations.
- Improved chat component to handle selected MCP services in message processing.
- Updated migration documentation to reflect new strategies and added MCP services migration files.
wizardchen