OPSX: Apply

A command that implements the tasks recorded for an OpenSpec change, a planned unit of software work. It finds the relevant instructions and tracks which tasks are complete.

In plain words
What is it for?
Use it to carry out the implementation tasks for a named OpenSpec change, using its status, context files, and task progress.
Why use it?
It removes the need to manually reconstruct the change plan before coding. It also handles selecting the correct change when the request does not identify one clearly.

Command for Claude Code

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add commands/designpipe/exfig/apply
Clone the repo
git clone --depth 1 https://github.com/DesignPipe/exfig

Made for: Claude Code.

Per session 15 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,066 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 84% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00015 $0.01066
Opus 5 $0.00008 $0.00533
Sonnet 5 $0.00003 $0.00213
Haiku 4.5 $0.00002 $0.00107

Measured yesterday against content hash dfa3a02a56d5, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

OPSX: Apply scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

84% identical to OPSX: Apply — 7 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.claude/commands/opsx/apply.md · 153 lines

How it starts

The opening of the file, as written. The whole thing — 153 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Implement tasks from an OpenSpec change.

Input: Optionally specify a change name (e.g., /opsx:apply add-auth). If omitted, check if it can be inferred from conversation context. If vague or ambiguous you MUST prompt for available changes.

Steps

  1. Select the change

    If a name is provided, use it. Otherwise:

    • Infer from conversation context if the user mentioned a change
    • Auto-select if only one active change exists
    • If ambiguous, run openspec list --json to get available changes and use the AskUserQuestion tool to let the user select

    Always announce: "Using change: " and how to override (e.g., /opsx:apply <other>).

  2. Check status to understand the schema

    openspec status --change "<name>" --json
    

    Parse the JSON to understand:

    • schemaName: The workflow being used (e.g., "spec-driven")
    • Which artifact contains the tasks (typically "tasks" for spec-driven, check status for others)
  3. Get apply instructions

    openspec instructions apply --change "<name>" --json
    

    This returns:

    • Context file paths (varies by schema)
    • Progress (total, complete, remaining)
    • Task list with status
    • Dynamic instruction based on current state

    Handle states:

    • If state: "blocked" (missing artifacts): show message, suggest using /opsx:continue
    • If state: "all_done": congratulate, suggest archive
    • Otherwise: proceed to implementation
  4. Read context files

    Read the files listed in contextFiles from the apply instructions output. The files depend on the schema being used:

    • spec-driven: proposal, specs, design, tasks
    • Other schemas: follow the contextFiles from CLI output
  5. Show current progress

    Display:

    • Schema being used
    • Progress: "N/M tasks complete"
    • Remaining tasks overview
    • Dynamic instruction from CLI
  6. Implement tasks (loop until done or blocked)

    For each pending task:

    • Show which task is being worked on
    • Make the code changes required
    • Keep changes minimal and focused
    • Mark task complete in the tasks file: - [ ]- [x]
    • Continue to next task

    Pause if:

    • Task is unclear → ask for clarification
    • Implementation reveals a design issue → suggest updating artifacts
    • Error or blocker encountered → report and wait for guidance
    • User interrupts
  7. On completion or pause, show status

    Display:

    • Tasks completed this session
    • Overall progress: "N/M tasks complete"
    • If all done: suggest archive
    • If paused: explain why and wait for guidance

Output During Implementation

## Implementing: <change-name> (schema: <schema-name>)

Working on task 3/7: <task description>
[...implementation happening...]
✓ Task complete

Working on task 4/7: <task description>
[...implementation happening...]
✓ Task complete

Output On Completion

## Implementation Complete

**Change:** <change-name>
**Schema:** <schema-name>
**Progress:** 7/7 tasks complete ✓

### Completed This Session
- [x] Task 1
- [x] Task 2
...

All tasks complete! You can archive this change with `/opsx:archive`.

Output On Pause (Issue Encountered)

## Implementation Paused

**Change:** <change-name>
**Schema:** <schema-name>
**Progress:** 4/7 tasks complete

### Issue Encountered
<description of the issue>

**Options:**
1. <option 1>
2. <option 2>
3. Other approach

What would you like to do?

Guardrails

  • Keep going through tasks until done or blocked
  • Always read context files before starting (from the apply instructions output)
  • If task is ambiguous, pause and ask before implementing
  • If implementation reveals issues, pause and suggest artifact updates
  • Keep code changes minimal and scoped to each task
  • Update task checkbox immediately after completing each task
  • Pause on errors, blockers, or unclear requirements - don't guess
  • Use contextFiles from CLI output, don't assume specific file names

Read the full file on GitHub · 153 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 153 lines · 15 tokens per session scan A dfa3a02a56d5

Subscribe to this mod's changes

OPSX: Apply is a command published in the GitHub repository DesignPipe/exfig (10 stars, last pushed 1mo ago), licensed MIT. It adds 15 tokens to every session and 1,066 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 84% identical to OPSX: Apply, differing in 7 lines, and is treated as a copy.