Skill tool returns `[object Promise]` instead of skill list

[BearHuddleston]

Description

When calling the skill tool for a skill that isn't in the session's discovered skills list, the error message shows [object Promise] instead of the actual available skills list.

Error: Skill "session-retrospective" not found. Available skills: [object Promise]

This appears to be an async/await issue where the Promise isn't being resolved before being interpolated into the error string.

Additional context

• Skills created before session start work correctly
• All skill files pass frontmatter validation (name, description present; name matches directory; regex pattern valid)
• Issue [BUG] Skill loading returns "[object Promise]" instead of actual skill list #6018 reported the same [object Promise] error and was closed on Dec 23, 2025 - this may be a regression or incomplete fix
• Separately, skills created mid-session aren't discoverable until a new session (which may be expected behavior), but the error message bug makes debugging confusing

Plugins

No response

OpenCode version

1.1.3

Steps to reproduce

1. Start an OpenCode session
2. Create a new skill mid-session:

   mkdir -p ~/.config/opencode/skill/test-skill
   cat > ~/.config/opencode/skill/test-skill/SKILL.md << 'EOF'
   ---
   name: test-skill
   description: A test skill created mid-session
   ---
   
   ## Test content
   EOF

3. Try to load the skill: skill({ name: "test-skill" })
4. Observe error: Error: Skill "test-skill" not found. Available skills: [object Promise]

Expected behavior

Error message should show the actual list of available skills:

Error: Skill "test-skill" not found. Available skills: github-cli, github-pr-review, senior-pr-review

Screenshot and/or share link

No response

Operating System

macOS (darwin)

Terminal

macOS Terminal

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• [BUG] Skill loading returns "[object Promise]" instead of actual skill list #6018: [BUG] Skill loading returns "[object Promise]" instead of actual skill list (similar error message, closed Dec 23, 2025 - may be a regression)
• Skill tool shows empty available_skills list #7069: Skill tool shows empty available_skills list (related to skill discovery issues)

Feel free to ignore if these don't address your specific case.

[rndmcnlly]

The [object Promise] error appears to have been fixed, but replaced with a different bug. On current dev, the error message reads:

```
Skill "blooper" not found. Available skills: 0, 1, 2, 3, 4
```

The root cause is in packages/opencode/src/tool/skill.ts, in the error path:

```ts
const available = await Skill.all().then((x) => Object.keys(x).join(", "))
```

Skill.all() returns Object.values(x.skills) — an array. Calling Object.keys(array) returns the numeric indices ("0", "1", "2", ...) rather than the skill names.

Fix:
```ts
const available = await Skill.all().then((x) => x.map((s) => s.name).join(", "))
```

This is a regression from whatever fix was applied for the [object Promise] issue — the await was added but the Object.keys call wasn't updated to account for the array return type.