Slack ACTION
Upload File
Upload a file (document, image, audio, etc.) to a Slack channel, group, or direct message, optionally with a comment. Use Send Message instead for text-only messages with no attachment.
Content can be a path to a file in /tmp or a URL; if the URL is a signed/presigned link whose path ends in an opaque ID or token rather than the real file name (e.g. a Google Cloud Storage or S3 URL with a ?X-Goog-Signature=... query string), Slack can't infer the file type from it and will show the upload as an unreadable binary — set File Name explicitly in that case. See the documentation- Action
- Writes data
- OAuth
- SDK
- MCP
IMPLEMENTATION
Call this tool
Connect a user's Slack account once, then configure and run Upload File from your backend or agent.
import { PipedreamClient } from "@pipedream/sdk"
const pd = new PipedreamClient({
projectId: process.env.PIPEDREAM_PROJECT_ID!,
clientId: process.env.PIPEDREAM_CLIENT_ID!,
clientSecret: process.env.PIPEDREAM_CLIENT_SECRET!,
projectEnvironment: "production",
})
const result = await pd.actions.run({
id: "slack_v2-upload-file",
externalUserId: "{external_user_id}", // any stable ID for this user in your system
configuredProps: {
slack_v2: { authProvisionId: "apn_xxxxxxx" },
conversation: "Channel",
content: "File Path or URL",
},
})
console.log(result)curl -X POST https://api.pipedream.com/v1/connect/{project_id}/actions/run \
-H "Content-Type: application/json" \
-H "X-PD-Environment: production" \
-H "Authorization: Bearer {access_token}" \
-d '{
"external_user_id": "{external_user_id}",
"id": "slack_v2-upload-file",
"configured_props": {
"slack_v2": { "authProvisionId": "apn_xxxxxxx" },
"conversation": "Channel",
"content": "File Path or URL"
}
}'// accessToken: mint a short-lived token with the Connect SDK — see the MCP guide
const transport = new StreamableHTTPClientTransport(
new URL("https://remote.mcp.pipedream.net/v3"),
{
requestInit: {
headers: {
Authorization: `Bearer ${accessToken}`,
"x-pd-project-id": "{project_id}",
"x-pd-environment": "production",
"x-pd-external-user-id": "{external_user_id}", // any stable ID for this user in your system
"x-pd-app-slug": "slack_v2",
},
},
},
)
const mcp = new Client({ name: "my-agent", version: "1.0.0" })
await mcp.connect(transport)
const { tools } = await mcp.listTools()
// listTools() hands your model this tool's input schema, so it can
// fill the arguments itself:
const result = await mcp.callTool({
name: "slack_v2-upload-file",
arguments: {
conversation: "Channel",
content: "File Path or URL",
},
})SCHEMA
Inputs
Pipedream supplies the connected account. Your application provides the operation-specific values below. Dynamic inputs are resolved against that user's account.
| Property | Type | Description |
|---|---|---|
conversation Channel | string | Prefer a channel ID (e.g. C1234567890) — use List Channels to look it up; it resolves instantly. A channel NAME (e.g. general or #general) is also accepted, but resolving it scans up to 5 conversations.list pages (~5,000 channels), which is slow and, on large workspaces, can be rate-limited or fail with a ConfigurationError if the channel is beyond that bound — pass the ID whenever you have it. Depending on the action, this may also accept a user ID (opens a direct message) or a group DM ID — use Find User by Email / Find User by ID to resolve a user ID, or List Group Conversations for group DM IDs. Required |
content File Path or URL | string | The file to upload. Provide either a file URL or a path to a file in the /tmp directory (for example, /tmp/myFile.txt). If the URL is a signed/presigned link (e.g. from Google Cloud Storage or S3), also set File Name — see this action's description for why. Required |
filename File Name | string | The name to give the uploaded file, including its extension (e.g. myFile.pdf). Defaults to the source file's name. Set this when Content is a signed/presigned URL whose path doesn't end in the real file name — otherwise Slack stores the file under whatever opaque ID or token is in the URL and can't tell its type. Optional |
initialComment Initial Comment | string | Message text to post alongside the file, introducing or describing it (e.g. Weekly sales report attached.). Optional |
syncDir SyncDir | dir | Optional |
REFERENCE
Tool details
Behavior hints are published with the component in the Pipedream registry and surface as MCP tool annotations, so an agent can reason about a tool before it calls it.
- Registry key
- slack_v2-upload-file
- Version
- 0.2.1
- App
- Slack
- Authentication
- OAuth
- Read-only
- No
- Destructive
- No
- Open world
- Yes
- Source
- View on GitHub ↗