Slack and Linear Integration Workflows

A customer reports a bug in your Slack support channel. Your product manager creates a Linear issue. An engineer triages it, assigns it, creates a branch, writes the fix, opens a PR, requests review, merges, and deploys. That is seven handoffs and a minimum of two days if everything goes smoothly. With Codex integrations, the PM assigns the Linear issue to Codex, Codex creates a cloud task, investigates the bug, proposes a fix, and posts a link to the completed task — all without an engineer touching the codebase.

What You’ll Walk Away With

• Working Slack and Linear integration workflows for delegating coding tasks
• Prompts optimized for each integration surface (Slack context vs Linear issue context)
• A triage automation pattern using Linear triage rules with Codex
• The MCP configuration for accessing Linear issues from local Codex sessions

The Workflow

Slack Integration

The Slack integration lets anyone on the team delegate coding tasks by mentioning @Codex in a channel or thread. Codex creates a cloud task, works in your repository, and posts results back to the thread.

Setup

1. Set up Codex cloud tasks at chatgpt.com/codex with a connected GitHub account and at least one environment.
2. Go to Codex settings and install the Slack app for your workspace.
3. Add @Codex to the channels where you want to delegate work.

Delegating from Slack

Tip

Copy-paste Slack message for bug fix:

@Codex The user profile update endpoint returns 200 but does not persist changes to the database. The issue is in the billing-api repo. Investigate the PUT /api/users/:id/profile handler, find the bug, fix it, and add a regression test.

Codex reads the message and thread history for context, picks the best matching environment, and starts a cloud task. When it finishes, Codex posts the results and a link to the task in the thread.

Key behaviors:

• Codex uses thread history as context, so earlier messages in the thread provide background. Summarize key details in your latest message so nothing is missed.
• Specify the repository if you have multiple environments: @Codex fix this in acme/billing-api.
• If Codex picks the wrong environment, reply in the thread: “Please run this in acme/billing-api (production)” and mention @Codex again.

Slack Patterns That Work Well

Bug triage from support channels:

@Codex A customer reports that invoice PDFs show the wrong tax rate when the billing address is in Canada. Investigate the PDF generation in acme/billing-api, find where the tax calculation happens, and check if Canadian tax rates are handled correctly. Report your findings but do not fix yet.

Quick analysis requests:

@Codex How does the webhook retry logic work in acme/payment-service? I need to understand the retry schedule and failure handling before we change it.

Follow-up in the same thread:

@Codex Based on your analysis, go ahead and fix the Canadian tax rate issue. Add tests covering US, Canadian, and EU tax calculations.

Linear Integration

The Linear integration lets you assign issues to Codex or mention @Codex in comments. Codex works like a team member — it picks up the issue, works in a cloud task, and posts progress updates back to the issue.

Setup

1. Set up Codex cloud tasks with a connected GitHub account and at least one environment.
2. Go to Codex settings and install Codex for Linear for your workspace.
3. Link your Linear account by mentioning @Codex in a comment on any Linear issue.

Assigning Issues to Codex

The simplest workflow: assign a Linear issue to Codex exactly like you would assign it to a teammate. Codex starts work and posts updates to the issue’s Activity tab.

Tip

Writing Linear issues for Codex:

Write the issue as if you were assigning it to a junior developer who has access to the codebase but no institutional knowledge. Be specific about:

• What the expected behavior should be
• What the current (broken) behavior is
• Which part of the codebase is relevant
• What “done” looks like (including tests)

Example issue title: “Fix: Canadian tax rate not applied to invoice PDFs”

Example issue description:

When a customer's billing address is in Canada, invoice PDFs should apply the 13% HST rate. Currently, they apply the US default rate of 0%.

Expected: Invoice PDF for Canadian customer shows 13% HST
Actual: Invoice PDF shows 0% tax

Relevant code: src/services/pdf/invoice-generator.ts, src/services/tax/calculator.ts
Done when: Canadian tax rate is applied correctly, unit tests cover CA/US/EU rates, existing tests still pass.

Automatic Triage with Linear Rules

For high-throughput teams, configure Linear triage rules to automatically assign qualifying issues to Codex:

1. In Linear, go to Settings > Your Teams > select your team
2. Open Workflow settings > Triage > turn on
3. Create a triage rule: Delegate > Codex

Now issues that enter triage are automatically assigned to Codex. The rule can filter by label, priority, or other properties, so you can route only specific types of issues to Codex (for example, issues labeled “bug” with priority “Low” or “Medium”).

Caution

Automatic triage delegation works best for well-defined, self-contained tasks. Complex features, architectural decisions, and cross-service changes should still go to human engineers. Start by routing only “bug” labeled issues to Codex and expand as you build confidence.

Mentioning @Codex in Comments

For issues already assigned to a human, you can still ask Codex for help by mentioning it in a comment thread:

@Codex Investigate the root cause of this issue. Check the webhook handler in src/routes/webhooks.ts and the retry logic in src/services/retry.ts. Report what you find but do not make changes yet.

After Codex replies, follow up in the same thread to continue the conversation:

@Codex Good analysis. Go ahead and implement the fix. Use the approach you described in option 2 (exponential backoff with jitter).

Local Linear Access via MCP

If you are working in the Codex App, CLI, or IDE extension and want to reference Linear issues during local development, configure the Linear MCP server:

codex mcp add linear --url https://mcp.linear.app/mcp

Or add it manually to ~/.codex/config.toml:

[mcp_servers.linear]
url = "https://mcp.linear.app/mcp"

Then log in: codex mcp login linear

With the Linear MCP connected, you can reference issues in local prompts:

Look up Linear issue ENG-1234. Read the description and implement the fix it describes. Follow the acceptance criteria listed in the issue.

When This Breaks

Codex picks the wrong environment in Slack. When you have multiple environments, Codex selects the one that best matches your request. If it picks wrong, reply with the specific environment: @Codex Please run this in acme/billing-api (staging).

Linear issue description is too vague. If the issue says “fix the bug” with no context, Codex will struggle to find the right code. Write issues with specific file paths, expected vs actual behavior, and reproduction steps. Codex reads the full issue content, so more detail means better results.

@Codex does not respond in Slack or Linear. Verify the integration is installed in your workspace settings. For Slack, ensure @Codex has been added to the channel. For Linear, verify your account is linked by mentioning @Codex in any issue comment.

Cloud task finishes but the code does not account for recent changes. Cloud tasks run against the default branch in your environment’s repo map. If the fix needs to apply to a feature branch, specify it in your message. For Linear issues, Codex uses the default branch of the first repository in the environment.

Enterprise Slack restrictions limit Codex responses. Some Enterprise workspaces restrict Codex from posting full answers in threads (to prevent code exposure). In these cases, Codex posts only a link to the task. Your admin controls this setting in ChatGPT workspace settings.

What’s Next

Scheduled Task Automation Combine integrations with automations for fully automated workflows

PR Automation Workflow Automate the PR lifecycle that follows from Codex cloud tasks