Slack

Workspace messaging API for sending messages, reading channel history, and managing channels. Use GET with query params for read endpoints (conversations.list, conversations.history, users.list, users.lookupByEmail) — POST with a JSON body silently drops filter params on some reads. Use POST with JSON body for writes (chat.postMessage, conversations.open). External Slack Connect users are NOT in users.list — resolve them via conversations.list + conversations.history user_profile blocks. search.messages requires the umbrella search:read scope (granular variants do not satisfy it). 6 example endpoints available through Lava’s AI Gateway. See the Slack API docs for full documentation.

This provider requires your own credentials — connect your API key or OAuth account before use.

This is a catch-all provider — any valid URL under https://slack.com is supported. 200+ Slack Web API methods. Construct URL as https://slack.com/api/{method_name}. See https://api.slack.com/methods for full reference. The endpoints below are curated examples.

Endpoints

Send a message to a channel

POST https://slack.com/api/chat.postMessage — Free

SDK
cURL

const data = await lava.gateway('https://slack.com/api/chat.postMessage', { body: {"channel":"C01234567","text":"Hello from Lava!"} });

curl -X POST "https://api.lava.so/v1/forward?u=https%3A%2F%2Fslack.com%2Fapi%2Fchat.postMessage" \
  -H "Authorization: Bearer $LAVA_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"channel":"C01234567","text":"Hello from Lava!"}'

Get channel message history. GET with query params — passing filters in a JSON POST body is silently ignored by Slack for some read endpoints.

GET https://slack.com/api/conversations.history?channel=C01234567&limit=10 — Free

SDK
cURL

const data = await lava.gateway('https://slack.com/api/conversations.history?channel=C01234567&limit=10', { method: 'GET' });

curl "https://api.lava.so/v1/forward?u=https%3A%2F%2Fslack.com%2Fapi%2Fconversations.history%3Fchannel%3DC01234567%26limit%3D10" \
  -H "Authorization: Bearer $LAVA_SECRET_KEY"

List channels in workspace. GET with query params — POST with `types` in a JSON body is silently dropped and returns public channels regardless of the filter. Use types=im,mpim for DMs and group DMs, public_channel for public channels, private_channel for private.

GET https://slack.com/api/conversations.list?types=public_channel&limit=100 — Free

SDK
cURL

const data = await lava.gateway('https://slack.com/api/conversations.list?types=public_channel&limit=100', { method: 'GET' });

curl "https://api.lava.so/v1/forward?u=https%3A%2F%2Fslack.com%2Fapi%2Fconversations.list%3Ftypes%3Dpublic_channel%26limit%3D100" \
  -H "Authorization: Bearer $LAVA_SECRET_KEY"

Open or resume a DM channel with a user. Required before chat.postMessage for DMs — pass the returned channel ID to chat.postMessage. Works even if the DM is already open (`already_open: true` is normal).

POST https://slack.com/api/conversations.open — Free

SDK
cURL

const data = await lava.gateway('https://slack.com/api/conversations.open', { body: {"users":"U01234567"} });

curl -X POST "https://api.lava.so/v1/forward?u=https%3A%2F%2Fslack.com%2Fapi%2Fconversations.open" \
  -H "Authorization: Bearer $LAVA_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"users":"U01234567"}'

List users in the workspace. Internal members only — external Slack Connect users do NOT appear here. Resolve external users via conversations.list + conversations.history user_profile blocks.

GET https://slack.com/api/users.list — Free

SDK
cURL

const data = await lava.gateway('https://slack.com/api/users.list', { method: 'GET' });

curl "https://api.lava.so/v1/forward?u=https%3A%2F%2Fslack.com%2Fapi%2Fusers.list" \
  -H "Authorization: Bearer $LAVA_SECRET_KEY"

Find a user by email. Confirm the exact email domain with the caller before using — corporate TLDs are often non-standard (e.g. .capital, .vc). GET with email as a query param.

GET https://slack.com/api/users.lookupByEmail?email=user@example.com — Free

SDK
cURL

const data = await lava.gateway('https://slack.com/api/users.lookupByEmail?email=user@example.com', { method: 'GET' });

curl "https://api.lava.so/v1/forward?u=https%3A%2F%2Fslack.com%2Fapi%2Fusers.lookupByEmail%3Femail%3Duser%40example.com" \
  -H "Authorization: Bearer $LAVA_SECRET_KEY"

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Endpoints

Send a message to a channel

Get channel message history. GET with query params — passing filters in a JSON POST body is silently ignored by Slack for some read endpoints.

List channels in workspace. GET with query params — POST with `types` in a JSON body is silently dropped and returns public channels regardless of the filter. Use types=im,mpim for DMs and group DMs, public_channel for public channels, private_channel for private.

Open or resume a DM channel with a user. Required before chat.postMessage for DMs — pass the returned channel ID to chat.postMessage. Works even if the DM is already open (`already_open: true` is normal).

List users in the workspace. Internal members only — external Slack Connect users do NOT appear here. Resolve external users via conversations.list + conversations.history user_profile blocks.

Find a user by email. Confirm the exact email domain with the caller before using — corporate TLDs are often non-standard (e.g. .capital, .vc). GET with email as a query param.

Next Steps

All Providers

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Get Started

AI Gateway

AI Spend

Monetize

Integration

SDK

Cookbook

Comparisons

​Endpoints

​Send a message to a channel

​Get channel message history. GET with query params — passing filters in a JSON POST body is silently ignored by Slack for some read endpoints.

​List channels in workspace. GET with query params — POST with types in a JSON body is silently dropped and returns public channels regardless of the filter. Use types=im,mpim for DMs and group DMs, public_channel for public channels, private_channel for private.

​Open or resume a DM channel with a user. Required before chat.postMessage for DMs — pass the returned channel ID to chat.postMessage. Works even if the DM is already open (already_open: true is normal).

​List users in the workspace. Internal members only — external Slack Connect users do NOT appear here. Resolve external users via conversations.list + conversations.history user_profile blocks.

​Find a user by email. Confirm the exact email domain with the caller before using — corporate TLDs are often non-standard (e.g. .capital, .vc). GET with email as a query param.

​Next Steps

All Providers

Forward Proxy

Endpoints

Send a message to a channel

Get channel message history. GET with query params — passing filters in a JSON POST body is silently ignored by Slack for some read endpoints.

List channels in workspace. GET with query params — POST with `types` in a JSON body is silently dropped and returns public channels regardless of the filter. Use types=im,mpim for DMs and group DMs, public_channel for public channels, private_channel for private.

Open or resume a DM channel with a user. Required before chat.postMessage for DMs — pass the returned channel ID to chat.postMessage. Works even if the DM is already open (`already_open: true` is normal).

List users in the workspace. Internal members only — external Slack Connect users do NOT appear here. Resolve external users via conversations.list + conversations.history user_profile blocks.

Find a user by email. Confirm the exact email domain with the caller before using — corporate TLDs are often non-standard (e.g. .capital, .vc). GET with email as a query param.

Next Steps