Linear Common Errors

Overview

Quick reference for diagnosing and resolving common Linear API errors.

Prerequisites

•Linear SDK or API access configured
•Access to application logs
•Understanding of HTTP status codes

Error Categories

Authentication Errors (401/403)

Invalid API Key

code

Error: Authentication required
Code: UNAUTHENTICATED

Causes:

•API key is invalid, expired, or revoked
•Key format is incorrect (should start with lin_api_)
•Environment variable not loaded

Solutions:

typescript

// Verify key format
const apiKey = process.env.LINEAR_API_KEY;
if (!apiKey?.startsWith("lin_api_")) {
  console.error("Invalid API key format");
}

// Test authentication
const client = new LinearClient({ apiKey });
try {
  await client.viewer;
  console.log("Authentication successful");
} catch (e) {
  console.error("Authentication failed:", e);
}

Permission Denied

code

Error: You don't have permission to access this resource
Code: FORBIDDEN

Causes:

•API key doesn't have required scope
•User not a member of the team/organization
•Resource belongs to different workspace

Solutions:

•Check API key permissions in Linear Settings > API
•Verify team membership
•Regenerate key with correct permissions

Rate Limiting Errors (429)

code

Error: Rate limit exceeded
Code: RATE_LIMITED
Headers: X-RateLimit-Remaining: 0, Retry-After: 60

Causes:

•Too many requests in time window
•Burst of requests without throttling

Solutions:

typescript

// Implement exponential backoff
async function withRetry<T>(
  fn: () => Promise<T>,
  maxRetries = 3
): Promise<T> {
  for (let i = 0; i < maxRetries; i++) {
    try {
      return await fn();
    } catch (error: any) {
      if (error?.extensions?.code === "RATE_LIMITED" && i < maxRetries - 1) {
        const delay = Math.pow(2, i) * 1000;
        console.log(`Rate limited, retrying in ${delay}ms...`);
        await new Promise(r => setTimeout(r, delay));
        continue;
      }
      throw error;
    }
  }
  throw new Error("Max retries exceeded");
}

Validation Errors (400)

code

Error: Variable "$input" got invalid value
Code: BAD_USER_INPUT

Common Validation Failures:

Field	Error	Fix
`teamId`	"Team not found"	Verify team exists and accessible
`priority`	"Invalid priority"	Use 0-4 (0=None, 1=Urgent, 4=Low)
`estimate`	"Invalid estimate"	Use team's configured values
`stateId`	"State not found"	State must belong to same team
`assigneeId`	"User not found"	User must be team member

Debug Validation:

typescript

async function createIssueWithValidation(input: {
  teamId: string;
  title: string;
  stateId?: string;
  assigneeId?: string;
}) {
  // Validate team exists
  const team = await client.team(input.teamId);
  if (!team) throw new Error(`Team not found: ${input.teamId}`);

  // Validate state belongs to team
  if (input.stateId) {
    const states = await team.states();
    if (!states.nodes.find(s => s.id === input.stateId)) {
      throw new Error(`State ${input.stateId} not in team ${team.key}`);
    }
  }

  // Validate assignee is team member
  if (input.assigneeId) {
    const members = await team.members();
    if (!members.nodes.find(m => m.id === input.assigneeId)) {
      throw new Error(`User ${input.assigneeId} not in team ${team.key}`);
    }
  }

  return client.createIssue(input);
}

GraphQL Errors

code

Error: Cannot query field "nonExistent" on type "Issue"
Code: GRAPHQL_VALIDATION_FAILED

Causes:

•Field name typo
•Querying deprecated field
•SDK version mismatch with API

Solutions:

bash

# Update SDK to latest
npm update @linear/sdk

# Check API schema
curl -H "Authorization: $LINEAR_API_KEY" \
  https://api.linear.app/graphql \
  -d '{"query": "{ __schema { types { name } } }"}'

Network Errors

code

Error: fetch failed
Cause: ECONNREFUSED / ETIMEDOUT

Solutions:

typescript

// Add timeout and retry
const controller = new AbortController();
const timeout = setTimeout(() => controller.abort(), 30000);

try {
  const response = await fetch("https://api.linear.app/graphql", {
    signal: controller.signal,
    // ... other options
  });
} finally {
  clearTimeout(timeout);
}

Diagnostic Commands

Test API Connection

bash

curl -s -H "Authorization: $LINEAR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"query": "{ viewer { name email } }"}' \
  https://api.linear.app/graphql | jq

Check Rate Limit Status

bash

curl -I -H "Authorization: $LINEAR_API_KEY" \
  https://api.linear.app/graphql
# Look for: X-RateLimit-Limit, X-RateLimit-Remaining

Validate Webhook Signature

typescript

import crypto from "crypto";

function verifyWebhookSignature(
  body: string,
  signature: string,
  secret: string
): boolean {
  const hmac = crypto.createHmac("sha256", secret);
  const digest = hmac.update(body).digest("hex");
  return crypto.timingSafeEqual(
    Buffer.from(signature),
    Buffer.from(digest)
  );
}

Error Handling Pattern

typescript

import { LinearClient, LinearError } from "@linear/sdk";

async function safeLinearCall<T>(
  operation: () => Promise<T>,
  context: string
): Promise<T> {
  try {
    return await operation();
  } catch (error) {
    if (error instanceof LinearError) {
      console.error(`Linear API Error in ${context}:`, {
        message: error.message,
        type: error.type,
        errors: error.errors,
      });

      // Handle specific error types
      switch (error.type) {
        case "AuthenticationError":
          throw new Error("Please check your Linear API key");
        case "RateLimitedError":
          throw new Error("Too many requests, please retry later");
        default:
          throw error;
      }
    }
    throw error;
  }
}

Resources

Next Steps

Set up comprehensive debugging with linear-debug-bundle.