# VS Code Copilot — Terminal Command Completion Not Reliably Detected (Discussion #161238)

## Metadata

| Field | Value |
|---|---|
| Institute | Molodetz Institute — Research & Retrieval Division |
| Subject | shell-multiplexer-auto-attach |
| Document type | Source Dossier |
| Tier | 1 |
| Source title | Copilot does not detect terminal command has completed or is not getting terminal output |
| Source URL | https://github.com/orgs/community/discussions/161238 |
| Source publisher / author | GitHub Community Discussions (Copilot) |
| Source type | forum thread |
| Source date (published) | Unknown — not stated |
| Date researched | 2026-10-09 |
| Researched by | tai (agent), model: Claude Sonnet 5, on behalf of retoor |
| Research method | web search synthesis |
| Confidence | Medium |
| Status | Active |

## Summary

Documents that VS Code's own terminal API does not provide a reliable signal for "has this shell command finished," forcing Copilot's agent integration to fall back on heuristics — direct evidence that even a tool built by the same vendor as the terminal itself struggles with reliable terminal-state detection.

## Key findings

- The unreliability isn't specific to third-party automation reading a terminal from outside; it's present even for first-party tooling with presumably the best possible access to the terminal's actual state.
- This is framed as an ongoing, acknowledged gap, not a solved problem with a known fix.

## Pros / strengths

- Strong corroborating evidence (from a major, well-resourced vendor's own open issue tracker) that reliable terminal-state/command-completion detection is a genuinely hard, unsolved-in-general problem — not something this proposal is failing to find an obvious answer to because of insufficient research.

## Cons / limitations / caveats

- About command-completion detection specifically, a related but distinct problem from this subject's main question (human vs. automation at shell *startup*) — cited here as supporting evidence for "terminal state detection is hard in general," not as a direct answer to the startup-detection question.

## Relevance to tai

Sets realistic expectations for the proposal: whatever detection heuristic ships, it should be designed to fail safe (default to NOT auto-wrapping when uncertain, with an easy manual opt-in) rather than promising perfect detection — because even well-resourced, first-party tooling hasn't solved the adjacent problem of terminal-state detection in general.

## Changelog

| Date | Change |
|---|---|
| 2026-10-09 | Initial dossier created. |