Query and mutate Linear data from a Node/TypeScript agent using the official @linear/sdk client instead of hand-written GraphQL

Documented steps

1. Install the client: npm install @linear/sdk.
2. Instantiate with a personal key (new LinearClient({ apiKey })) or an OAuth token (new LinearClient({ accessToken })).
3. Read data via direct property access for singletons (const me = await linearClient.viewer) or connection methods for lists (const issues = await linearClient.issues()), then read issues.nodes.
4. Pass required identifiers as positional args (linearClient.team("team-id")) and optional query params as a trailing object (linearClient.projects({ first: 50 })). Chain across related models, e.g. (await linearClient.viewer).assignedIssues().
5. Mutate with createX/updateX/archiveX helpers, e.g. linearClient.createIssue({ teamId, title }) or linearClient.updateUser(me.id, { displayName }) — equivalently entity.update({...}) / entity.archive().
6. Always check the mutation payload's `success` boolean before using the returned entity, e.g. if (commentPayload.success) return commentPayload.comment.
7. For lists, use the built-in cursor helpers: linearClient.issues({ after: cursor, first: 10 }) then issues.fetchNext() and issues.pageInfo.{hasNextPage,endCursor}.
8. Official docs: https://linear.app/developers/sdk and https://linear.app/developers/sdk-fetching-and-modifying-data