Shreyas Patil has released session-bridge, an open-source plugin for Claude Code that lets isolated coding agent sessions talk to each other on the same machine. The problem it solves is concrete: when engineers run <a href="/news/2026-03-14-recon-tmux-tui-claude-code-sessions">separate Claude Code sessions</a> across a shared library and its consumer app, or a backend and frontend, each session has no awareness of the other's context. Session-bridge adds a local filesystem-based messaging layer — using atomic file writes and UUID message identifiers stored under ~/.claude/session-bridge/ — that lets agents query one another directly, without spawning additional processes or incurring extra API calls.
The core mechanic is a /bridge listen command that puts one Claude Code session into a continuous polling loop, ready to answer queries from peer sessions. When a connected session sends a question via /bridge ask, the listening agent formulates the response using its live conversation context — meaning it can accurately describe breaking changes it authored, API schemas it has already reasoned through, or migration steps it has worked out, rather than relying on stale documentation or approximations. The plugin also supports natural language invocation: developers can tell their agent to "ask the library about X" without explicitly typing bridge commands, letting the tool blend into agentic workflows with minimal manual orchestration.
Session-bridge takes a different path from Anthropic's Model Context Protocol (MCP), the open standard Anthropic released in late 2024 for connecting AI assistants to external data sources and tools. MCP defines a network-addressable client-server protocol layer; session-bridge skips that entirely and uses the local filesystem as its sole transport. The difference matters beyond cost. MCP tool invocations are stateless by design — each call returns a result with no persistent memory of the server's own reasoning — whereas session-bridge's value is that the responding agent carries its full live context, including intermediate conclusions not yet written to any file. MCP has no provision for one Claude session to act as a peer to another; the protocol always treats Claude as the client and external tools as the server.
The plugin requires only jq as an external dependency and is available on Patil's GitHub. Known limitations: local-only operation, no Windows support, no message encryption, and session state that doesn't survive terminal closure. All of these follow from the filesystem-primitive design. If Anthropic extends MCP to support stateful session-to-session messaging — something <a href="/news/2026-03-14-calyx-ghostty-based-macos-terminal-with-liquid-glass-ui-and-ai-agent-ipc-via-mcp">developers are already beginning to explore</a> — session-bridge's approach would have a shorter shelf life. For now it fills a real gap, and the fact that a community developer built it before any official tooling existed says something about how fast demand for agent-to-agent coordination is outpacing what Anthropic currently ships.