feat(tool/bash): expose session context via environment variables

[oussamadouhou]

Summary

Injects OPENCODE_SESSION_ID and OPENCODE_MESSAGE_ID into subprocess environment when executing bash commands, enabling spawned processes to identify their parent session context.

Motivation

Currently, when OpenCode spawns bash subprocesses, those processes have no way to identify which session they belong to. This limits:

• Session self-awareness: Agents cannot query their own session history
• Cross-session communication: Scripts cannot interact with session APIs
• Context propagation: Tooling cannot correlate subprocess activity with sessions

Changes

• packages/opencode/src/tool/bash.ts: Added OPENCODE_SESSION_ID and OPENCODE_MESSAGE_ID to the subprocess environment
• packages/opencode/test/tool/bash.test.ts: Added test verifying environment variable injection

Use Cases

# Agent can now read its own session history
echo "Current session: $OPENCODE_SESSION_ID"

# Scripts can interact with session APIs
curl "http://localhost:4096/session/$OPENCODE_SESSION_ID/messages"

# Cross-session communication patterns
opencode-session-id info $OPENCODE_SESSION_ID

Testing

• Added unit test that verifies both environment variables are correctly passed to subprocess
• All existing bash tool tests continue to pass (9/9)

[github-actions]

The following comment was made by an LLM, it may be inaccurate:

No duplicate PRs found

[oussamadouhou]

Closing - will resubmit with expanded scope after further review