Developer Tools Articles
65 articles across AI Catchup's news, guides, tutorials, and comparisons.
All Developer Tools articles
Claude Code Hooks: A Practical Guide With Six Recipes
Claude Code hooks run your own shell commands, HTTP endpoints, MCP tools, prompts, or agents at fixed points in a session. You define them in settings.json, narrow them with matchers, and block actions with exit code 2 or JSON. Exit 0 is not approval, and a hook allow never loosens your deny rules.
How to Build a Claude Code Mod: Files, Hooks, State, and Testing
A Claude Code mod is a plugin whose JavaScript or TypeScript hooks run inside your session. Ask Claude to write one, or create plugin.json, hooks/hooks.json, and a module that exports register. Load it with --plugin-dir, keep state in $.state, then check it with claude plugin validate and claude plugin test.
Cursor SDK Adds Live Agent Steering and Background Subagent Results
Cursor SDK 1.0.31 returns background subagent results to the parent run and adds MCP tool annotations for custom tools. Live steering with run.steer() and replaceable system prompts are documented in the TypeScript SDK reference for local agents. As of October 7, 2026, the changelog is at 1.0.35 and 1.0.32 changed how steering behaves while an agent waits on background subagents.
Claude Code Mods Let Developers Customize the CLI and Desktop App
Anthropic introduced Claude Code mods as a plugin-based way to customize how Claude Code behaves and looks. Small JavaScript or TypeScript modules can add interface elements, change tool calls, or replace built-in features. Mods run with Claude Code's access to your machine, so review their source before installing.
Claude Code Can Build Evaluations and Improve Apps Against Held-Out Tests
Anthropic's Claude API skill gives Claude Code two evaluation workflows: `/claude-api build-eval` creates an evaluation in a codebase, and `/claude-api hillclimb` proposes one change at a time against it. The hillclimb holds out test cases, reverts changes that do not improve the test set, and reports uncertainty against the baseline.
OpenAI Developers Names 10 WebMCP Challenge Winners
OpenAI Developers announced 10 WebMCP Challenge winners. The projects show websites exposing structured tools that agents can use alongside people, from editable floor plans and wedding seating to 3D scans, notebooks, and fantasy maps.
Claude Opens a Plugin Directory Submission Portal for MCP and Skills
Anthropic launched a Claude directory submission portal on September 25, 2026. Developers on paid Claude plans can submit a remote MCP connector or a GitHub-hosted plugin bundle that packages MCP servers and skills, follow validation and safety review, publish approved versions, and see listing and usage analytics.
Anthropic Resumes Billing for Claude Refusals Before Output in Three Safeguard Categories
Anthropic resumed billing for Claude requests refused before any output when its safeguards classify them as biology, frontier LLM development, or reasoning extraction. The charge uses the model's normal rates across platforms. Other pre-output refusals remain unbilled, but still count against rate limits.
Cursor Rollouts Watches Deployments for Regressions Before Users See Them
Cursor introduced Rollouts, a Teams and Enterprise bot that follows a change from pull request to production. It writes an editable monitoring plan, checks deploys against logs, metrics, and traces, and reports verified health, regressions, or inconclusive results. It does not merge or roll back on its own.
Claude Code Adds Configurable AGENTS.md Support
Claude Code 2.1.277 adds AGENTS.md support through a built-in mod. By default Claude Code reads AGENTS.md when a project has no CLAUDE.md or CLAUDE.local.md, and /config changes the behavior. Since 2.1.281 it also works on Amazon Bedrock, Google Vertex AI, Microsoft Foundry, LLM gateways, and with telemetry disabled.
Claude Code Projects Turn One Conversation Into Parallel Cloud Sessions
Anthropic's redesigned Projects beta gives Claude Code one coordinating conversation that delegates work to parallel threads. Threads are usually cloud sessions, which Anthropic's docs now list as available, no longer in research preview, on Pro, Max, and Team and for eligible Enterprise seats. A project can also run a thread on your own machine through Remote Control.
Claude Managed Agents Adds a Terminal Session Viewer and Auto Permission Mode
Claude Managed Agents now includes a terminal workflow for attaching to live sessions and a local web session viewer. Anthropic also added an auto permission mode that evaluates each agent or MCP tool call against the intent in user.message and runs, denies, or pauses for approval.
OpenAI Welcomes the Git AI Team Behind an Open-Source Agent Attribution Tool
OpenAI says Aidan Cunniffe and Sasha Varlamov from the Git AI team have joined OpenAI. Their open-source Git extension tracks AI-generated code at line level, linking it to the agent, model, and prompts that produced it, with commands for attribution stats and AI-aware blame.
Claude Code Adds Plugin Evals for Regression Testing and No-Plugin Baselines
Claude Code now includes `claude plugin eval`, a testing workflow for plugin and skill authors. The command can create cases and graders, run a plugin in isolated non-interactive sessions, compare results with a no-plugin baseline, generate an HTML report, and support CI gates for plugin changes. Evals require Claude Code v2.1.269 or later and consume model usage.
Cursor Projects Give a Coordinator Agent a Long-Lived Body of Work
Cursor's Projects beta moves beyond one chat at a time: a coordinator agent keeps context over months, delegates implementation and testing to subagents, shares research and artifacts across cloud and local machines, and can watch PRs, Slack, or a schedule for recurring work.
OpenAI Opens Its Codex-Powered Agents API to All Developers in Public Beta
OpenAI's Agents API is now in public beta for all developers. The managed service uses the Codex harness to run long-lived cloud agents, coordinate parallel subagents, compact context across long sessions, and work in OpenAI-hosted, VPC, or partner-provided sandboxes.
Claude Code Desktop Adds Pop-Out Panes for Diff and Terminal Work
ClaudeDevs says Claude Code Desktop can now pop out any pane into its own window. You can move a diff or terminal to another screen while Claude keeps working, dock it back later, and run sessions side by side or stacked.
OpenAI Shares a Defense Factory Playbook for Agentic Cyber Defense
OpenAI is sharing a Defense Factory playbook that connects security tools, skills, reproducible environments, and agents into a continuous loop for discovering, validating, assigning, remediating, and independently verifying vulnerabilities.
Claude's ant CLI Can Now Manage Agent Resources as Code
Anthropic added `ant apply` to the Claude CLI, letting teams declare Managed Agent environments, agents, skills, memory stores, and deployments in a repository and reconcile them with the Claude API.
OpenAI Launches GPT-6 Astra for Computer Use and Complex Work
OpenAI launched GPT-6 Astra on September 3, 2026, as a model for computer use, browsing, software engineering, cybersecurity, science, and complex professional workflows. Access started with a limited set of organizations; Astra is now available in ChatGPT Work and Codex, the OpenAI API, Microsoft Foundry, and Amazon Bedrock.
Anthropic Open-Sources a Commerce Agents Blueprint for Claude
Anthropic's open-source Claude Commerce Agents blueprint, released September 2, 2026, ships a shopping agent and a merchant agent that run on the Messages API, the Agent SDK, or Managed Agents, four runnable verticals, a Claude Code plugin, and an engineering deep-dive. It is Apache-2.0, unmaintained by design, and no demo places an order or charges a card.
Cursor Cloud Agents Can Now Run on Self-Hosted Machines
Cursor Cloud Agents can now execute on machines that a team manages, including dynamically scaling pools inside its network. The execution environment moves to the team's infrastructure while Cursor continues to handle the agent loop, inference, and planning.
Claude Code Desktop Can Now Resume Sessions Started in the Terminal
Claude Code can now move a terminal-started session into the Claude Code desktop app. Anthropic says users can type /resume, choose a CLI session, and continue with the full conversation and context intact.
Cursor Cloud Agents Can Now Start Apps From Scratch
Cursor Cloud Agents can now begin a web app without an existing repository. The workflow can create an Origin repository, preview the result, and publish it to Vercel without requiring a local setup first.
ChatGPT Workspaces Can Sync GitHub Plugin Marketplaces Daily
ChatGPT workspace admins and owners can now import plugin marketplaces from public or private GitHub repositories and keep them synchronized automatically. The feature gives teams a central way to distribute Codex and Claude-compatible plugins while keeping installation policies and app permissions under workspace control.
OpenAI Plans to End Direct Cursor Model Access on November 12
OpenAI plans to end Cursor's direct access to OpenAI models. November 12, 2026 is proposed, and as of October 9 neither company has confirmed it. Only OpenAI models picked inside Cursor are affected, about 5% of its traffic. Local Chat and Agent can keep OpenAI through your own API key or the Codex extension; Tab, Auto and Cloud Agents cannot.
Claude Makes Enterprise-Managed Auth for MCP Connectors Generally Available
Anthropic says enterprise-managed auth for MCP connectors is now generally available. Claude Team and Enterprise admins can centralize authorization through their identity provider, while users receive connector access automatically without individual OAuth consent flows.
OpenAI Brings GPT-5.6 Model Family to Kiro for Spec-Driven Coding
OpenAI says the GPT-5.6 model family, including Sol, Terra, and Luna, is now available in Kiro. The OpenAI-AWS update targets structured, long-running software work and reports roughly an 82% cost reduction per successful Terminal-Bench 2.1 task for GPT-5.6 Terra in Kiro's spec-driven environment.
Claude Code Remote Control Can Start Sessions From Your Phone
As of September 2026, a machine running claude remote-control appears as a device card at the top of the Code tab in the Claude app: tap it, pick a directory, and a session starts on that machine. Anthropic's Week 34 digest also took Remote Control out of research preview. Code and files stay local.
OpenAI Adds API-Key Spend Dashboards and Hard Limits
OpenAI's API platform now lets teams group Usage and Costs data by API key and set monthly organization or project spend limits. The dashboard feature helps identify which apps and workloads drive spend, while a hard limit can stop affected API traffic with a documented 429 error after the cap is reached.
Claude Security Brings Mythos Scans to Enterprise Customers, Now on Mythos 5.1
Claude Security scans now run on Claude Mythos 5.1 for all Claude Enterprise customers; they moved there from Mythos 5, which powered them from August 21. The public-beta product scans connected codebases, returns CWE, confidence, severity, and suggested-fix details, and opens fixes in Claude Code on the web without exposing the Mythos model directly.
Claude Platform Makes Computer Use, Browser Use, Skills, and Files Generally Available
Anthropic says computer use, browser use, the Skills API, and the Files API are now generally available on the Claude Platform, combining multi-action software control with versioned skills and reusable files for production agents.
OpenAI Adds Transparent Backgrounds to GPT-Image-2 in API Preview
OpenAI added transparent-background output in preview for gpt-image-2 and gpt-image-2-2026-04-21 across the Images API and Responses API image-generation tool, with PNG or WebP output required.
Claude Managed Agents Add Memory Stores, Domain Controls, and a Redesigned Console
Anthropic's Claude Managed Agents updates let self-hosted sandbox sessions attach memory stores, restrict web_search and web_fetch with allowed_domains or blocked_domains, and inspect multi-agent sessions in a redesigned Claude Console viewer.
Cursor Cloud Agents Add Event Triggers, Long-Lived Goals, and Isolated Subagents
Cursor says Cloud Agents can now pick up work from events, keep working toward a long-lived goal, monitor pull requests, watch Slack threads, run scheduled tasks, and launch subagents in isolated virtual machines. The same update adds skill-based Custom Modes and less disruptive steering while an agent is working.
OpenAI's GPT-5.6 Builder's Guide Shows How to Make Agents More Efficient
OpenAI's GPT-5.6 builder's guide lays out a Responses API architecture for longer-running agents: persist reasoning, compact context, delegate work across agents, and move deterministic tool processing into code. OpenAI reports that these patterns raised GPT-5.6 Sol's ARC-AGI-3 score from 13.3% to 38.3% while using roughly 6x fewer output tokens.
Claude Code Auto-Continues When Usage Limits Reset, On by Default
Claude Code waits in the open session and continues your task automatically when a claude.ai usage limit resets. It is on by default from version 2.1.234 in interactive sessions signed in with a claude.ai subscription. Turn it off in /config under 'Continue automatically at usage limit' or set autoContinueAtUsageLimit to false. It resumes work; it does not raise the limit.
Cursor Welcomes Firetiger to Connect Coding Agents to Production
Cursor says the Firetiger team joined Cursor to bring production-operation agents closer to coding agents. Firetiger's agents monitor rollouts, catch regressions, investigate incidents, and pass findings back to coding agents. The Change Monitors the announcement called coming soon shipped on September 23, 2026 as Cursor Rollouts, on Teams and Enterprise plans.
Cursor Is Now Part of SpaceX
Cursor says its acquisition by SpaceX has officially closed. The Cursor team will join SpaceXAI, with the companies aiming to combine SpaceX's computing capacity and Cursor's product experience to build stronger, more economical models and make them useful in products such as Cursor and Grok.
Cursor Cloud Agents Start Up to 3x Faster With Builds
Cursor says Cloud Agents can start up to 3x faster with Builds, ready-to-use copies of development environments prepared in the background. Builds keep agents on the latest successful environment, expose logs and version history in the dashboard, and are now the default path for every Cloud Agent environment.
ChatGPT Desktop App Arrives on Linux in Preview
OpenAI is previewing the ChatGPT desktop app for Linux. The app brings ChatGPT, ChatGPT Work, and Codex to supported Linux systems, with official posts listing Ubuntu 24.04 and 26.04, Debian 13, and Fedora 43 and 44, plus .deb and .rpm packages for x64 and ARM64.
Codex Can Import Workflows From Other AI Agents
OpenAI now lets the ChatGPT desktop app and Codex CLI import supported setup and recent work from other agents. The desktop app can import from Claude Code, Claude Cowork, and Cursor, while Codex CLI supports Claude Code and Cursor, with automatic updates and import history available in the desktop app.
OpenAI Brings Codex Security Review to GitHub Pull Requests
Codex Security Review is OpenAI’s research-preview workflow for deeper security analysis of GitHub pull requests. It uses the diff, repository context, and optional threat-model guidance, then reports actionable findings in the pull request and a fuller report in Codex. Enterprise, Business, Edu, and Pro users can configure it; Plus is excluded.
Claude Code Sessions Can Now Message Each Other
Claude Code lets independent sessions discover and message one another. As of September 2026, a session can start a conversation with a session on the same machine, on another of your machines, or on Claude Code on the web; same-machine messaging works on macOS, Linux, WSL 2, and native Windows and on every provider. Messaging is on with nothing to enable, and incoming messages can be accepted, held, or refused per session.
Agent Plugins: An Open Standard for Skills and MCP
OpenAI Developers introduced Agent Plugins, an open, vendor-neutral package format for sharing Agent Skills and MCP server configurations across compatible agent clients.
Cursor Router: Auto Balance, Auto Intelligence, and Cost Modes
Cursor Router is the routing system behind Auto, and Cursor documents it as available only on Teams and Enterprise plans. Open the model picker, select Auto, and pick Cost, Balance, or Intelligence under Optimize For. Every mode bills at the list price of whichever model the request is routed to.
Cursor SDK Bridge Opens Agent Control to Rust, Go, and More
Cursor has open-sourced an SDK Bridge that exposes a stable sdk.v1 protocol for driving Cursor agents from Rust, Go, Java, and other languages. Adapters run a small local bridge and communicate over Connect RPCs, while the bridge handles the connection to Cursor's API.
Cursor Agents Can Now Act Across Google Workspace
Cursor says new Google Workspace plugins give its coding agents direct access to Gmail, Google Drive, and Google Calendar. The plugins can search, read, draft, send, create, and manage Workspace data from inside Cursor, and install from the Cursor Marketplace or the Customize page.
OpenAI Details GPT-Live’s Full-Duplex Voice Architecture
OpenAI says GPT-Live is a third-generation voice system that can listen and speak at the same time, keep media flowing while deeper reasoning and tool use run asynchronously, and power ChatGPT Voice today. The architecture is also intended to underpin an upcoming GPT-Live API.
Cursor Says Cloud Agents Use 20-30% Fewer Tokens
Cursor said on August 3, 2026 that its Cloud Agents are 20-30% more token efficient, and 80% more efficient on runs with computer use, crediting better MCP, skills, and computer-use handling. A September 23 agent-harness update later reported a further 7% cut in token costs without lower agent quality.
GPT-5.4 Left ChatGPT-Signed-In Codex on August 31, 2026
OpenAI said GPT-5.4 and GPT-5.4 mini would stop being available in Codex for users signed in with ChatGPT on August 31, 2026, and that date has now passed. The models remain available through the OpenAI API and Codex sessions authenticated with an API key, confirmed September 1, 2026. Recommended replacements: GPT-5.6 Terra and GPT-5.6 Luna.
MCP 2026-07-28 Moves to a Stateless Core as Claude Rolls Out Support
Anthropic says the MCP 2026-07-28 specification moves the Model Context Protocol from a bidirectional stateful design to a request/response model, adds versioned extensions for MCP Apps and Tasks, and aligns authorization with production OAuth 2.0 and OIDC deployments.
OpenAI Releases Codex Security CLI for Repository Scans and CI Checks
OpenAI says its open-source Codex Security CLI can scan repositories, track findings across runs, verify fixes, and add security checks to CI/CD. The beta CLI requires Codex Security access and is built for teams that want code-aware security review in the terminal.
Codex ImageGen Adds a Lightbox + Canvas Workflow for Image Editing on Desktop
OpenAI Developers announced a new ImageGen workflow in Codex: a lightbox viewer and a canvas-style editing surface designed for direct, point-and-edit changes (erase, annotate, place text) instead of long prompt rewrites.
Claude Code Artifacts Expand to Pro and Max Plans (Private Until You Share)
Claude Code Artifacts, which launched for Team and Enterprise, reached Pro and Max plans in July 2026. On Pro and Max an artifact is private until you share it, and a public link is the way to share it; sharing with specific people or a whole organization is a Team and Enterprise feature.
Anthropic raises Claude API rate limits and consolidates tiers into Start, Build, and Scale
Claude Platform usage tiers are Start, Build, and Scale, and Sonnet and Haiku rate limits match Opus at every tier, including Opus 5.5, Sonnet 5.5, and Haiku 5.5. Tier placement is automatic, based on usage history rather than spend, but each tier still carries a monthly spend cap.
Claude Code Adds Artifacts: Live, Shareable Pages for PR Walkthroughs and Dashboards
Artifacts in Claude Code turn an in-progress session into a live web page that updates as the session works. Launched in June 2026 as a beta for Team and Enterprise with org-only sharing, they are now on Pro, Max, Team, and Enterprise, and an artifact can be shared to a public link anyone can open.
Claude Design's `/design-sync` Makes Claude Design and Claude Code a Two-Way Workflow
As of September 2026, `/design-sync` is a Claude Code command that converts your repo's design system and uploads it to Claude Design, so designs start from your real components. `/design` in Claude Code creates, edits, and syncs designs, and a finished design hands off to Claude Code through the Export menu. It needs a claude.ai account.
Cursor Origin Enters Early Beta: Code Hosting, Pull Requests, and GitHub Sync
Cursor's Origin, a Git forge built for agents, began rolling out in early beta on all paid plans on August 17, 2026 and is still in early beta. It hosts repositories, pull requests, code browsing and search, and GitHub mirroring, with Cursor agents in every repo. Free plans are excluded, and enterprise admins can opt out.
Cursor Shared Canvases: Publish an Agent Canvas and Share It With Your Team via URL
Cursor added shared canvases -- you can now share a canvas from Cursor with your team by generating a link to a live snapshot that teammates open in the browser. Recipients view it read-only in the Cursor Dashboard, so you distribute a working dashboard or report instead of a full chat thread. Shared canvases are available on Pro, Teams, and Enterprise plans.
Claude Platform's 'ant' CLI Brings the Full Claude API to Your Terminal
Anthropic's 'ant' CLI exposes every Claude API resource as a terminal subcommand. As of September 2026 you install it through Homebrew, curl, or Go, authenticate by browser login, API key, or Workload Identity Federation, manage agents as code with 'ant apply' (CLI 1.30.0 or later), and run a self-hosted Managed Agents worker with 'ant beta:worker poll' or 'ant beta:worker run'.
Cursor Canvases: When to Ask the Agent for a UI Instead of Text
Cursor canvases are agent-generated interactive artifacts -- dashboards, reports, audits -- that render beside the chat. Cursor saves each one to your workspace canvas list, so you can reopen, edit, and rerun it later with fresh data. Publishing a canvas as a browser link for teammates needs a paid plan and a team.
Inside Claude Code's Rebuilt Desktop: Parallel Agents, Drag-Drop Panes, Side Chat
Anthropic rebuilt the Claude Code desktop app on April 14, 2026 around parallel agent workflows: a multi-session sidebar, drag-and-drop panes, an in-app file editor, integrated terminal, side chat, three view modes, and SSH on macOS. Four months on the app also creates routines and local scheduled tasks, browses external sites, and controls your computer.
How to Build Your Own MCP Server: A Beginner's Guide
To build an MCP server in TypeScript, install the v2 SDK package @modelcontextprotocol/server with Zod v4, register each tool with server.registerTool and a Zod input schema, serve it over stdio, then add it to Claude Code with claude mcp add or a .mcp.json entry. A one-tool server is about 50 lines.
Cursor vs Claude Code in 2026: Which AI Coding Tool Is Better?
Neither tool is terminal-only or editor-only any more: Cursor ships a CLI and Claude Code ships a desktop app, IDE extensions and a browser surface. Choose Cursor for inline tab autocomplete and cross-lab model choice, though OpenAI plans to end Cursor's direct model access on a proposed November 12; choose Claude Code for one agent across surfaces.