- Introduced structured error handling for MCP upstream fetches, distinguishing between network errors (`-32010`) and upstream errors (`-32011`). This allows the agent to provide more informative feedback based on the type of failure encountered.
- Updated the `fetchUpstreamJson` function to throw `McpUpstreamError` with detailed error data, including hints and next actions for specific tools.
- Enhanced the `TOOL_HINTS` mapping to provide tool-specific guidance for handling errors, improving the agent's ability to respond to various failure scenarios.
- Added comprehensive unit tests to validate the new error handling logic and ensure correct behavior across different error cases.
- Updated documentation in `docs/agents/hermes-skill.md` to include a new section on structured MCP errors, detailing the error codes and their meanings.