skillctx-ify

skillctx-ify

Migrate a skill to use skillctx for skill variable resolution.

When to Use

• Making a skill portable (removing hardcoded values)
• Setting up a new skill to use skillctx
• User says "skillctx-ify" or "migrate skill to skillctx"

Prerequisites

• Python 3.10+ (for the resolver script)
• Target skill must be installed and discoverable by the agent host

Workflow

Phase 1: Scan and classify

1. Locate the target skill: Find the skill directory by name. Follow symlinks to the actual directory.

2. Check for prior migration: Check for <!-- skillctx:begin --> marker in the skill's SKILL.md. If found, check metadata.skillctx.version in frontmatter.

   • If version matches current: report already migrated, stop.
   • If version is older: suggest running skillctx-sync to update.

3. Read the skill files: Read SKILL.md and all referenced files in the skill directory. Also read references/known-patterns.md for classification guidance.

4. Identify candidates: Scan the content for hardcoded values that are user-specific or environment-specific — usernames, Slack channel IDs, filesystem paths, org names, etc. For each candidate, determine:

   • Is this actually a skill variable or a generic/example string? Use context (tool calls vs prose), repetition, and specificity to decide.
   • What category does it belong to in vars? Use existing config categories as a guide. Defaults: identity, slack, paths, blog.
   • What should the binding key be named? See Binding Key Naming below.

5. Read existing config: Read ${XDG_CONFIG_HOME:-~/.config}/skillctx/config.json if it exists. If not, note it needs to be created. Reuse existing vars when the value already exists in the config — don't create duplicates.

Phase 2: Confirm and rewrite

6. Present proposed changes to user in a table like this:

   Hardcoded value	File:line	Binding key	Var dotpath	New?
   CABC123DEF	SKILL.md:42	channel_id	vars.slack.channel_id	yes
   alice	SKILL.md:10	github_username	vars.identity.github_username	no (exists)

   Wait for user confirmation before proceeding.

7. Rewrite skill files:

   a) Replace hardcoded values with {binding_key} placeholders. The placeholder is a literal string in the skill file — it gets resolved at runtime by the resolver script.

   Before: Post to #eng-standup (CABC123DEF) After: Post to {channel_name} ({channel_id})

   b) Inject the setup block near the top of SKILL.md (after the frontmatter and title), wrapped in comment markers:

   <!-- skillctx:begin -->
   ## Setup
   Locate this skill's directory (the folder containing this SKILL.md), then run the
   resolver script from there:
   
   python <skill-dir>/scripts/skillctx-resolve.py resolve <skill-name>
   
   The resolver outputs each binding as `key: value` (one per line). For list values, it outputs JSON (e.g., `orgs: ["org-a", "org-b"]`). Substitute each `{binding_key}` placeholder below with the resolved value.
   
   If any values are missing or the user requests changes, use:
   python <skill-dir>/scripts/skillctx-resolve.py set <skill-name> <key> <value>
   <!-- skillctx:end -->
   

   c) Update the skill's description to remove migrated values and replace them with placeholders.

   d) Add metadata.skillctx.version: "0.1.0" to the skill's frontmatter.

Phase 3: Write-back

8. Copy resolver script: Copy scripts/resolve.py (from this skill's directory) into the target skill's scripts/ directory as skillctx-resolve.py. Create scripts/ if it doesn't exist. Make it executable.

9. Update config file: Write the updated config with new vars and bindings. Create the directory (mkdir -p) if needed.

10. Report: Show what was extracted, bindings created, and files changed.

Binding Key Naming

Binding keys are the names used as {placeholders} in the skill and as keys in skills.<name> in the config. They should be:

• Descriptive of the role, not the value. Use channel_id not standup_channel_id — the skill doesn't care which channel, just that it has one.
• Scoped to the skill's perspective. If a skill posts to one channel, channel_id is fine. If it uses two channels for different purposes, disambiguate: post_channel_id, alert_channel_id.
• snake_case, lowercase, no prefixes like var_ or ctx_.
• Stable. Once a skill is migrated, renaming keys breaks existing configs. Choose names that won't need to change if the underlying value changes.

Examples:

Hardcoded value	Good binding key	Bad binding key	Why
CABC123DEF	channel_id	slack_standup_id	role > source
alice	github_username	user	too vague
~/Sync/notes	notebook_path	dropbox_path	tied to provider
["acme", "widgets-inc"]	github_orgs	orgs_list	redundant suffix

Error Handling

Error	Action
Skill directory not found	Report error, suggest checking the skill name
Skill already migrated (current version)	Report and stop
Skill already migrated (older version)	Suggest running skillctx-sync
No candidates found	Report that skill has no hardcoded values. Add empty binding entry to config.
Config file malformed	Report the JSON parse error, suggest manual fix