docs: update Learning Hub with CLI v1.0.40–v1.0.41 features (#1626)

Add documentation for features shipped in Copilot CLI v1.0.40 and
the v1.0.41 prerelease builds that weren't yet covered in the Hub:

- copilot-configuration-basics.md: document --attachment flag for
  attaching images/documents in prompt mode (-p)
- automating-with-hooks.md: extend the prompt mode security callout
  to cover the new GITHUB_COPILOT_PROMPT_MODE_EXTENSIONS env var
  (user extensions load by default; project extensions need opt-in)
- building-custom-agents.md: note that ACP clients receive the
  agent's live plan in real time for multi-step tasks (v1.0.40+)

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
This commit is contained in:
github-actions[bot]
2026-05-06 10:05:48 +10:00
committed by GitHub
parent ce516684b5
commit 8788c5d142
3 changed files with 15 additions and 5 deletions
@@ -3,7 +3,7 @@ title: 'Automating with Hooks'
description: 'Learn how to use hooks to automate lifecycle events like formatting, linting, and governance checks during Copilot agent sessions.'
authors:
- GitHub Copilot Learning Hub Team
lastUpdated: 2026-05-04
lastUpdated: 2026-05-05
estimatedReadingTime: '8 minutes'
tags:
- hooks
@@ -277,7 +277,7 @@ exit 1 # deny (let the user decide interactively)
> ```bash
> GITHUB_COPILOT_PROMPT_MODE_REPO_HOOKS=true copilot -p "..." --no-ask-user
> ```
> This is a secure-by-default change: it prevents untrusted repository hooks from firing silently when a user runs a quick prompt command in an unfamiliar repository. Similarly, workspace MCP servers are disabled in prompt mode by default; opt in with `GITHUB_COPILOT_PROMPT_MODE_WORKSPACE_MCP=true`.
> This is a secure-by-default change: it prevents untrusted repository hooks from firing silently when a user runs a quick prompt command in an unfamiliar repository. Similarly, workspace MCP servers are disabled in prompt mode by default; opt in with `GITHUB_COPILOT_PROMPT_MODE_WORKSPACE_MCP=true`. Extensions follow a mixed model (v1.0.41+): **user-level extensions** (from `~/.copilot/`) load automatically in prompt mode, but **project-level extensions and management tools** are disabled by default — opt in with `GITHUB_COPILOT_PROMPT_MODE_EXTENSIONS=true` to load them.
### Handling Tool Failures with postToolUseFailure