[BUG] apm install fails when agent description contains YAML special characters

[kuisathaverat]

Describe the bug

When an agent file has a : in any fiels like description or name the apm install fails with an error like the following:

-- Diagnostics --
  [x] 1 package failed:
    +- github/awesome-copilot/agents/swe-subagent.agent.md -- Failed to integrate primitives from cached package: Invalid YAML format in 
/private/tmp/test/apm_modules/github/awesome-copilot-swe-subagent/apm.yml: mapping values are not allowed here
  in "/private/tmp/test/apm_modules/github/awesome-copilot-swe-subagent/apm.yml", line 3, column 72

This is the definition that beraks apm install https://github.com/github/awesome-copilot/blob/main/agents/swe-subagent.agent.md?plain=1

To Reproduce
Steps to reproduce the behavior:

1. run the following script

cd /temp
mkdir test
cd test
cat << EOF > apm.yml
name: AI Assets
version: 1.0.0
description: Test bug
type: hybrid
dependencies:
  apm:
    - github/awesome-copilot/agents/swe-subagent.agent.md#2f4953242f2fc5256c8b1416d0136cb73e68640e
  mcp: []
scripts: {}
EOF

apm install --target all

4. See error

[>] Installing dependencies from apm.yml...
  [+] github.com/github/awesome-copilot/agents/swe-subagent.agent.md#2f4953242f2fc5256c8b1416d0136cb73e68640e #2f4953242f2fc5256c8b1416d0136cb73e68640e (cached)

[i] Added apm_modules/ to .gitignore

-- Diagnostics --
  [x] 1 package failed:
    +- github/awesome-copilot/agents/swe-subagent.agent.md -- Failed to integrate primitives from cached package: Invalid YAML format in 
/private/tmp/test/apm_modules/github/awesome-copilot-swe-subagent/apm.yml: mapping values are not allowed here
  in "/private/tmp/test/apm_modules/github/awesome-copilot-swe-subagent/apm.yml", line 3, column 72

[!] Installed 1 APM dependency with 1 error(s).

Expected behavior

The agent is installed without errors

Environment (please complete the following information):

• OS: macOS
• Python Version: 3.13.11
• APM Version: 0.8.11

Logs

[>] Installing dependencies from apm.yml...
  [+] github.com/github/awesome-copilot/agents/swe-subagent.agent.md#2f4953242f2fc5256c8b1416d0136cb73e68640e #2f4953242f2fc5256c8b1416d0136cb73e68640e (cached)

[i] Added apm_modules/ to .gitignore

-- Diagnostics --
  [x] 1 package failed:
    +- github/awesome-copilot/agents/swe-subagent.agent.md -- Failed to integrate primitives from cached package: Invalid YAML format in 
/private/tmp/test/apm_modules/github/awesome-copilot-swe-subagent/apm.yml: mapping values are not allowed here
  in "/private/tmp/test/apm_modules/github/awesome-copilot-swe-subagent/apm.yml", line 3, column 72

[!] Installed 1 APM dependency with 1 error(s).

[sergio-sisternes-epam]

Thanks for reporting this, @kuisathaverat! The root cause is confirmed -- APM's virtual package generator used f-string interpolation for apm.yml, which breaks when frontmatter fields contain YAML special characters like :.

This is being fixed in #707 by @edenfunf, which replaces the f-string approach with proper yaml.safe_dump serialization via the project's yaml_to_str() helper. That PR is approved and queued to merge.

Accepting this as a confirmed bug. It will auto-close when #707 lands.