Webhook
An HTTP callback mechanism in which a system automatically sends a POST request to a specified URL when a particular business event occurs. It is commonly used to implement event-driven integration between systems.
Core Facts
Event triggers rely on the Webhook mechanism — an external application sends an HTTP request to the URL provided by N8N when the event occurs, and N8N starts the corresponding Workflow upon receiving it.
A webhook is essentially an HTTP callback: after a repository detects an event such as a code push, it sends a POST request to a pre-configured URL.
A Webhook is a kind of reverse API: rather than n8n actively requesting an external service, it provides a dedicated URL externally, and when any service initiates an HTTP request to that address, the n8n workflow can be triggered.
Timeline (last 90 days)
OpenMail supports pushing inbound email to developers' code via Webhook or WebSocket.
The WeChat notification bot sends messages by posting a JSON payload via Webhook, commonly seen in WeCom group bots or third-party relay services.
A Webhook address is equivalent to a password; once leaked, anyone can send messages to the group chat, so it is recommended to store it in environment variables or a configuration file.
In Agent systems, Webhooks make changes in the external world directly become the Agent's startup signal; cron is a schedule-based timer trigger suitable for periodic tasks; combined, the two can cover both event-driven and time-driven autonomous trigger scenarios.
When handling webhooks under Vercel's stateless function model, events may be delivered more than once, so processing logic needs to be idempotent.
Automatic webhook registration depends on the provider offering, via its API, the ability to programmatically create, update and delete webhook subscriptions.
Alert verification actions can be bound to webhook destinations rather than a global switch, allowing the same monitor to be configured with multiple destinations in parallel: a paging channel with a Critical Only filter and an archive channel that receives all alerts.
Event-driven architectures (such as webhooks or message queues) are a more elegant way to wake agents, but they require agent platforms to provide callback interfaces, and most personal assistants currently do not expose such capabilities.
Both Linear and Jira provide APIs and Webhooks, allowing external tools to read task status, update tickets, or embed links.
The scheduler is responsible for triggering Agent runs by time or event, such as cron timers and Webhooks, enabling the Agent to execute tasks periodically in the background without manual instructions.
40 more timeline events
All Facts (20)
Event triggers rely on the Webhook mechanism — an external application sends an HTTP request to the URL provided by N8N when the event occurs, and N8N starts the corresponding Workflow upon receiving it.
75%VerifiedA webhook is essentially an HTTP callback: after a repository detects an event such as a code push, it sends a POST request to a pre-configured URL.
75%VerifiedA Webhook is a kind of reverse API: rather than n8n actively requesting an external service, it provides a dedicated URL externally, and when any service initiates an HTTP request to that address, the n8n workflow can be triggered.
70%VerifiedWebhook signature verification typically uses the HMAC-SHA256 algorithm, with the signature covering the timestamp and request body content, and the receiver locally recomputes the signature with the shared secret and compares it.
65%VerifiedWebhooks must undergo signature verification; otherwise, anyone can forge requests to wake up an agent, creating security risks.
65%VerifiedWebhook requests may be sent repeatedly due to timeouts, retries, or the at-least-once delivery semantics of message queues.
65%VerifiedIn n8n, each functional unit placed inside a workflow is called a node, and the process runs by connecting nodes
65%VerifiedThe Webhook trigger node in n8n has two modes: test URL and production URL; the test URL path contains the word 'test' and is primarily used for debugging during the development phase in conjunction with the Execute Workflow button.
65%VerifiedWebhook triggers are suitable for scenarios that require real-time response to external events, while scheduled trigger nodes are suitable for scenarios such as batch processing and periodic synchronization.
65%VerifiedCompared to polling, webhooks require no repeated client-side status queries, resulting in lower latency and less resource consumption.
65%Verifiedn8n supports three types of triggers: Webhook triggers, polling triggers, and scheduled triggers (executed via Cron expressions).
65%VerifiedA webhook is a reverse API mechanism in which a business system sends an HTTP POST request to a pre-registered URL when a status change occurs, with latency typically within the sub-second range.
65%VerifiedWebhooks use a push model, actively sending an HTTP POST request to a target URL when an event occurs in the source system, with significant advantages over polling in terms of latency and resource consumption.
65%VerifiedWhen n8n passes back results, the HTTP Request node should be used rather than the Respond to Webhook node
65%VerifiedIf credits are deducted only at the Webhook callback stage, the task will already be complete when a user has insufficient credits, meaning AI computing resources have been consumed but the credits cannot be deducted.
65%Unverified在AI SaaS架构中，n8n工作流通过Webhook与前端通信，而非通过表单触发
90%Unverified飞书提供完整的机器人消息推送接口，允许外部系统通过HTTP请求将结构化内容直接发送到指定群组或文档
90%Unverified成熟的系统通常采用Webhook加轮询兜底的双重机制来确保任务状态获取的可靠性
85%Unverified积分预检和积分扣除是两个独立的环节，预检在任务提交前拦截积分不足的请求，扣除在Webhook回调时执行
85%Unverified在典型的AI SaaS架构中，主流做法是客户端提交任务后立即获得任务ID，后端异步处理，处理完成后通过Webhook回调通知结果
85%