Cyrus Setup LinearBLOCK

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The instruction file, verbatim from the audited commit — this is the text the model reads, and the surface the audit's instruction layer examines. Quoted here so you can judge it without cloning anything.

---
name: cyrus-setup-linear
description: Create a Linear OAuth application and configure Cyrus to use it — supports agent-browser automation or guided manual setup.
---

**CRITICAL: Never use `Read`, `Edit`, or `Write` tools on `~/.cyrus/.env` or any file inside `~/.cyrus/`. Use only `Bash` commands (`grep`, `printf >>`, etc.) to interact with env files — secrets must never be read into the conversation context. Never scrape, extract, or read secret values from web pages — guide the user to copy them manually.**

# Setup Linear

Creates a Linear OAuth application and configures credentials so Cyrus can receive webhooks and respond to issues.

## Step 1: Check Existing Configuration

```bash
grep -E '^LINEAR_CLIENT_ID=' ~/.cyrus/.env 2>/dev/null
```

If `LINEAR_CLIENT_ID` is already set, check if OAuth is also complete:

```bash
grep -q '"workspaces"' ~/.cyrus/config.json 2>/dev/null && echo "configured" || echo "not configured"
```

If both are set, inform the user:

> Linear is already configured. Skipping this step.
> To reconfigure, remove `LINEAR_CLIENT_ID`, `LINEAR_CLIENT_SECRET`, and `LINEAR_WEBHOOK_SECRET` from `~/.cyrus/.env` and re-run.

Skip to completion.

## Step 2: Get CYRUS_BASE_URL

Read the base URL from the env file (set by `setup-endpoint`):

```bash
grep '^CYRUS_BASE_URL=' ~/.cyrus/.env | cut -d= -f2-
```

This is needed for the callback and webhook URLs.

## Step 3: Create Linear OAuth App From Manifest

Linear OAuth apps must be created from a manifest-backed setup URL. Do not create the app from scratch or fill each field manually. The manifest flow keeps the app configuration reproducible and avoids drift in callback, webhook, and event type settings.

### 3a. Build the manifest URL

Generate a JSON OAuth app manifest and encode it into Linear's `manifest` query parameter:

```bash
CYRUS_BASE_URL="<CYRUS_BASE_URL>" \
AGENT_NAME="<AGENT_NAME>" \
AGENT_DESCRIPTION="<AGENT_DESCRIPTION>" \
node <<'NODE'
const fs = require("node:fs");

const baseUrl = process.env.CYRUS_BASE_URL.replace(/\/+$/, "");
const agentName = process.env.AGENT_NAME || "Cyrus";
const agentDescription =
	process.env.AGENT_DESCRIPTION || "AI coding agent for automated development";

const manifest = {
	$schema: "https://linear.app/.well-known/oauth-app-manifest.schema.json",
	schemaVersion: "1.0.0",
	distribution: "private",
	display: {
		description: agentDescription,
	},
	developer: {
		name: "Self-hosted",
	},
	oauth: {
		client_name: agentName,
		client_uri: "https://github.com/ceedaragents/cyrus",
		redirect_uris: [`${baseUrl}/callback`],
		grant_types: ["authorization_code"],
	},
	webhook: {
		enabled: true,
		url: `${baseUrl}/linear-webhook`,
		resourceTypes: [
			"AgentSessionEvent",
			"AppUserNotification",
			"PermissionChange",
			"Issue",
		],
	},
};

const manifestJson = JSON.stringify(manifest, null, 2);
const manifestUrl = `https://linear.app/settings/api/applications/new?manifest=${encodeURIComponent(JSON.stringify(manifest))}`;

fs.writeFileSync("/tmp/cyrus-linear-oauth-app-manifest.json", `${manifestJson}\n`);
fs.writeFileSync("/tmp/cyrus-linear-oauth-app-url.txt", `${manifestUrl}\n`);

console.log(manifestJson);
console.log(`\n${manifestUrl}`);
NODE

LINEAR_MANIFEST_URL="$(cat /tmp/cyrus-linear-oauth-app-url.txt)"
```

The same URL is now stored in `LINEAR_MANIFEST_URL` for automation commands and in `/tmp/cyrus-linear-oauth-app-url.txt` for manual copy/paste. The JSON is stored in `/tmp/cyrus-linear-oauth-app-manifest.json` for review/debugging only; do not ask the user to fill the OAuth app form manually from it.

If `<AGENT_NAME>` contains the word "Linear" or a URL, choose a different OAuth application name before building the manifest. Linear rejects OAuth client names with those values.

Determine which browser automation mode to use (see orchestrator rules):

1. If `claude-in-chrome` MCP tools are available → use **Path A-1** (claude-in-chrome)
2. If `agent-browser` is installed (`which agent-browser`) and a Chrome debug session is connected → use **Path A-2** (agent-browser)
3. Otherwise → use **Path B** (manual)

### Path A-1: claude-in-chrome Automation

Use the `mcp__claude-in-chrome__*` tools to navigate and interact with the user's existing Chrome browser. The user is likely already signed in to Linear.

Navigate to `LINEAR_MANIFEST_URL`. The page should open with the manifest-applied OAuth app configuration already populated.

Review only non-secret fields:

- Application name matches `<AGENT_NAME>`
- Developer name is `Self-hosted`
- Developer URL is `https://github.com/ceedaragents/cyrus`
- Redirect callback URLs contains `<CYRUS_BASE_URL>/callback`
- Webhook is enabled with URL `<CYRUS_BASE_URL>/linear-webhook`
- Event types include Agent session events, Inbox notifications, Permission changes, and Issues
- Public/distribution is private or disabled

If the user is not signed in, pause and ask them to sign in. After review, click **Create**. **Do NOT screenshot credential pages or attempt to scrape secrets.** Proceed to Step 4.

### Path A-2: agent-browser Automation

If `agent-browser` is connected to a Chrome debug session, automate the Linear app creation.

#### 3b. Navigate to the manifest URL

```bash
agent-browser navigate "$LINEAR_MANIFEST_URL"
```

Wait for page to load. Take a screenshot to verify you're on the right page and logged in.

#### 3c. Review and create

Review the same non-secret manifest-applied fields listed in Path A-1. If the page asks the user to sign in, pause and let them complete sign-in. Click **Create**.

After creation, Linear redirects to the app settings page. **Do NOT screenshot credential pages or attempt to scrape secrets.** Proceed to Step 4.

### Path B: Manual Guided Setup

Guide the user through manual creation:

> ### Create a Linear OAuth Application
>
> 1. Open this manifest-backed Linear app creation URL:
>
>    `<LINEAR_MANIFEST_URL>`
>
> 2. Sign in to Linear if prompted, then review the pre-filled settings:
>    - *

BLOCKgrade D · trust 69/100 Do not install this without reading the findings. The audit found something that could harm you or your machine.

What the source does

Filesystem

none-observed

Network

none-observed

Shell

none-observed

Dependencies

pinned

Secrets in source

none-found

Findings (6)

## Step 4: Collect Credentials

.claude/skills/cyrus-setup

.claude/skills/cyrus-setup-claude-auth

.claude/skills/cyrus-setup-endpoint

.claude/skills/cyrus-setup-github

.claude/skills/cyrus-setup-gitlab

Gates applied: no_behavioural_pass.