Fix Copilot agent path to use identifier instead of full path

[Copilot]

The Copilot CLI's --agent flag expects an agent identifier (filename without extension), not a full file path. This fix extracts the identifier from the agent file path for Copilot while maintaining full path usage for Claude and Codex engines that need to read file content.

Root Cause

The Copilot CLI discovers agents automatically and references them by identifier:

# Incorrect - passes full path
copilot --agent "${GITHUB_WORKSPACE}/.github/agents/cli-consistency-checker.md"
# Error: No such agent: /workspaces/gh-aw/.github/agents/cli-consistency-checker.md

# Correct - passes identifier
copilot --agent cli-consistency-checker
# Works!

Changes

• pkg/workflow/engine_helpers.go:

  • Added ExtractAgentIdentifier() to extract filename without extension
  • Updated ResolveAgentFilePath() to properly quote full paths for Claude/Codex

• pkg/workflow/copilot_engine.go: Updated to use agent identifier instead of full path

• pkg/workflow/engine_helpers_test.go: Added tests for identifier extraction and updated existing tests

• pkg/workflow/engine_agent_import_test.go: Updated Copilot test to expect agent identifier

Result

Copilot engine: Uses agent identifier

--agent cli-consistency-checker

Claude/Codex engines: Use full path with proper quoting for file reading

"${GITHUB_WORKSPACE}/.github/agents/test-agent.md"

Original prompt

Investigate incorrect encoding of the encoding GITHUB_WORKSPACE variable.

See error https://github.com/githubnext/gh-aw/actions/runs/19285890449/job/55146633195#step:24:1

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[pelikhan]

@copilot the --agent option takes the agent identifier, ie. the file name without extension. Here is a cli output to test the feature::

@pelikhan ➜ /workspaces/gh-aw (copilot/investigate-github-workspace-encoding) $ copilot --agent /workspaces/gh-aw/.github/agents/cli-consistency-checker.md -p "hello"
No such agent: /workspaces/gh-aw/.github/agents/cli-consistency-checker.md, available: cli-consistency-checker, copilot-add-safe-output-type, create-agentic-workflow, create-shared-agentic-workflow, improve-json-schema-descriptions, setup-agentic-workflows, shell-2-script, technical-doc-writer
@pelikhan ➜ /workspaces/gh-aw (copilot/investigate-github-workspace-encoding) $ copilot --agent cli-consistency-checker -p "hello"

[Copilot]

@copilot the --agent option takes the agent identifier, ie. the file name without extension. Here is a cli output to test the feature::

...

Fixed in 0e4255e. The Copilot CLI now receives the agent identifier cli-consistency-checker instead of the full path.

Claude and Codex engines continue using the full path since they read file content with awk.

[Copilot]

Pull Request Overview

This PR fixes how the Copilot CLI agent path is passed by using the agent identifier (filename without extension) instead of the full file path. The Copilot CLI auto-discovers agents and expects identifiers, while Claude and Codex engines need full paths to read file content.

Key Changes

• Added ExtractAgentIdentifier() function to extract filename without extension from agent file paths
• Updated ResolveAgentFilePath() to properly quote full paths with ${GITHUB_WORKSPACE} for Claude/Codex
• Updated Copilot engine to use agent identifier instead of full path
• Updated tests to match new expectations

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
pkg/workflow/engine_helpers.go	Added ExtractAgentIdentifier() function and updated ResolveAgentFilePath() quoting
pkg/workflow/copilot_engine.go	Changed to use ExtractAgentIdentifier() for Copilot CLI --agent flag
pkg/workflow/engine_helpers_test.go	Added tests for identifier extraction and updated path format tests
pkg/workflow/engine_agent_import_test.go	Updated Copilot test to expect identifier, Claude/Codex tests updated for new quoting
.github/workflows/technical-doc-writer.lock.yml	Regenerated lock file (appears incomplete - see bug below)
.github/workflows/cli-consistency-checker.md	Removed agent import, inlined agent instructions
.github/workflows/cli-consistency-checker.lock.yml	Regenerated lock file after removing agent import

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