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lemlist Signal Agents API

Signal Agents (watch lists) - create and configure watches, list the available signal types and filters, read detected signals, and push external signals.

lemlist Signal Agents API is one of 22 APIs that lemlist publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

Tagged areas include Signal Agents and Buying Signals. The published artifact set on APIs.io includes an OpenAPI specification.

This API exposes 10 operations across 7 paths, and defines 16 schemas. It is described by OpenAPI 3.2.0, at version 1.0.0.

Requests are made against a single base URL, https://api.lemlist.com/api.

10 operations 7 paths 16 schemas 1 DELETE6 GET1 PATCH2 POST

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.2.0
API Version
1.0.0
Base URL
https://api.lemlist.com/api
Authentication
HTTP Basic
Resource Areas
1

Authentication & Security 1

lemlist Signal Agents API declares 1 security scheme for authenticating requests. It accepts HTTP basic authentication (basicAuth). By default, every request must be authenticated.

Paths & Operations 10

Across 7 paths, the API surfaces 10 operations — 1 DELETE, 6 GET, 1 PATCH, 2 POST. Each is listed below with its method, path, parameters, and response codes.

Signal Agents 10
GET
/watchlist/signals
Get Signal Agent signals
9 params → 200400401404405500
POST
/watchlist/{watchListId}/external-signals
Push external signals
1 param body → 200400401404500
GET
/watchlist
List Signal Agents
4 params → 200400401500
POST
/watchlist
Create Signal Agent
body → 201400401402429500
PATCH
/watchlist
Update Signal Agent
body → 200400401404409500
DELETE
/watchlist
Delete Signal Agent
1 param → 200400401500
GET
/watchlist/history
Get Signal Agent configuration history
3 params → 200400401404500
GET
/watchlist/library
List available signal types
→ 200401500
GET
/watchlist/filters
List allowed filters per signal type
1 param → 200400401500
GET
/watchlist/filter-values
Autocomplete filter values
2 params → 200400401502500

Schemas 16

The contract defines 16 schemas that model the data the API accepts and returns. The most detailed are WatchListConfigHistoryEntry (12 properties), SignalSchema (11 properties), WatchListSchema (10 properties), WatchListFilterDescriptor (7 properties). Each schema is shown below with its type and property counts.

WatchListSchema
object
A Signal Agent (watch list) configuration.
10 properties
WatchListConfigHistoryEntry
object
A past configuration version of a Signal Agent, active during [startDate, endDate).
12 properties
WatchListListMeta
object
1 property
WatchListApiListWatchListsResponse
object
2 properties
WatchListApiFilterValuesResponse
object
1 property
WatchListApiFiltersResponse
object
1 property
WatchListApiHistoryResponse
object
2 properties
WatchListApiFetchSignalsResponse
object
Paginated response containing signals detected by Signal Agents
2 properties
WatchListApiDeleteWatchListResponse
object
1 property
WatchListApiWatchListResponse
object
1 property
WatchListFilterDescriptor
object
Describes a filter that can be set on a Signal Agent of a given type.
7 properties
WatchListLibraryEntry
object
3 properties
WatchListFilter
object
A filter narrowing which entities or events a Signal Agent tracks. in includes matching values, out excludes them.
3 properties 1 required
WatchListApiLibraryResponse
object
1 property
ExternalSignalPushResponse
object
5 properties
SignalSchema
object
A signal detected by a Signal Agent representing a tracked event (hiring, LinkedIn activity, website visit, etc.)
11 properties 8 required

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

lemlist-signal-agents-api-openapi.yml Raw ↑

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Where this information came from

This is an independent, third-party profile of lemlist Signal Agents API, published by API Evangelist. We do not operate, host, resell, or support these APIs, and we are not affiliated with or endorsed by the company unless stated above. Everything here is built from publicly available information — the company's own site, developer portal, documentation, public repositories, and the specifications it publishes for public use. Nothing is obtained by breaching a system, defeating an access control, or using credentials.

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