# How to let your agent read logs and fix a failed deploy. URL: https://antideploy.com/blog/how-to-let-your-coding-agent-read-logs-and-fix-a-failed-deploy When a deploy fails, your agent reads the reason and the logs, fixes the code and deploys again. Here is what it reads and what to say. ## At a glance - **A reason in one sentence**: Every failed deploy says why - **Logs on demand**: Up to 300 lines at a time - **Fix and deploy again**: Failed deploys never count - **Some fixes are automatic**: For causes that are certain Published 7 October 2026. Facts checked 7 October 2026. 4 min read. ## The short answer When a deploy fails, your coding agent reads the failure reason, reads the app's logs, fixes the project and deploys again. You can say "the last deploy failed, fix it" and let it run. A failed deploy never counts against your plan, so it can try as many times as it needs. > **Say this to your agent** > > The last deploy failed. Read the reason and the logs, fix the cause, and deploy again. ## What your agent reads - **The failure reason.** Every failed deploy records a one-sentence reason in the deploy history. It names the cause, such as a lock file that does not match package.json, and says what to change. - **The build log.** A failed deploy keeps the end of the build log and what the app printed while Antideploy tried to start it. - **The app's logs.** What the running app printed, newest last. The default is 100 lines and the most it returns at once is 300. - **Health.** Whether the app is running, degraded, down or unknown, and when it was last checked. - **Metrics.** Requests, server errors and response times, for up to 30 days, 7 by default. Your agent checks them when you say the site is slow. ## The loop, step by step ### 1. Read the reason first The agent reads the failure sentence from the deploy history before it does anything else. Most failures name their own cause, and the sentence is written to be acted on. ### 2. Read the logs beside it The reason says what failed. The logs say what the app was doing. The most common failure on Antideploy is an app that builds correctly and never starts listening on its port. The logs show whether it crashed on boot or listened on the wrong port. ### 3. Fix the project The agent changes the code, the lock file or the configuration. Redeploying the same code unchanged reproduces the same failure, so the agent should change something first. ### 4. Deploy again The agent sends the new version and watches it. If it fails again, it reads the new reason. A failed deploy is free, so there is no cost to trying. ## What Antideploy fixes by itself Some failures are not your code's fault, and some have a fix that is certain from the log alone. - **Platform faults are retried.** If a deploy fails because of the platform and not your code, Antideploy builds the same version again after a few minutes. The retry does not count against your deploys and does not email you. - **A lock file that does not match.** If `package-lock.json` is out of date, Antideploy installs from `package.json` for that build, in its own copy of the source, and tells you. - **Peer dependency conflicts.** If npm refuses a conflict between two packages, Antideploy installs with `legacy-peer-deps` for that build, and tells you. - **Blocked pnpm scripts and Prisma versions.** Antideploy allows install scripts that pnpm blocked, and pins the Prisma tool to the version your code uses. These repairs happen in a copy of your source. Antideploy never edits your repository. You still get a note about what it changed, and the right fix in your own repository is to commit the corrected file. ## What to do when it keeps failing - **Change one thing, then deploy.** If the reason is the same twice, the fix did not take. - **Ask for the logs.** Say "show me the last 200 log lines" and read them yourself. - **Check the exact message.** The Fix an error section of this blog has a page for each common message, with the fix. - **Do not paste secrets into the chat.** Your agent never needs to read a value back. ## Here's where it stops. A platform that only tells you what it is good at is one you find the edges of in production. These are the ones to know before your first deploy. ### One deploy at a time A second deploy of the same app is refused until the first finishes. Different apps deploy side by side. ### 10 deploys a month on Free Only successful deploys of apps with a server count. Static sites never do, and a failed deploy is free. ## Fix-loop questions, answered. Anything else? Write to us and a person answers. [support@antideploy.com](mailto:support@antideploy.com) ### Does a failed deploy cost me anything? No. Failed deploys never count against your plan, on any plan. ### Can my agent read a secret to debug a problem? No. Variables are write-only. It can list the names that are set, and it can see which names your code expects that are not set yet. ### How many deploys can it try? Up to 20 an hour for one app. One deploy at a time per app, so a second one waits until the first finishes. ### Where do I see the failure reason myself? In the deploy history in the console, and in the email you receive when a deploy fails. ### What if the logs are empty? Then the app printed nothing, or it never started. The failure reason says which. If the app never started listening on its port, see the page on that error. ## More guides, and the platform. Each platform page covers one part of Antideploy: what it does, where it stops and the questions people ask. [See the whole platform](https://antideploy.com/platform), or [all the guides](https://antideploy.com/blog). - [How to deploy an app without opening a dashboard](https://antideploy.com/blog/how-to-deploy-an-app-without-opening-a-dashboard): Your agent deploys, reads logs and sets things up. The few things that stay in a browser, and what to say. - [Why does my app work on localhost but not online?](https://antideploy.com/blog/why-does-my-app-work-on-localhost-but-not-online): Nine common reasons, how to check each one, and how to fix it. - [Your app built successfully but never started listening on its port](https://antideploy.com/blog/your-app-built-successfully-but-never-started-listening-on-its-port): The app built but never answered on its port. Read PORT, listen on 0.0.0.0 and check the logs. - [Deployments](https://antideploy.com/platform/deployments) - [Logs and monitoring](https://antideploy.com/platform/logs-and-monitoring) - [Agent API](https://antideploy.com/platform/agent-api) - [Security checks](https://antideploy.com/platform/security-checks) Facts on this page were checked against the live platform on 7 October 2026. ## Deploy something. Start with one sentence. Paste one sentence into your coding agent, click Approve once, and get a live link. No card, no trial clock. To set this up, give your coding agent this sentence: ```text Set this project up to deploy on Antideploy. Fetch https://antideploy.com/agent.md and follow it. ```