Skip to main content
You can use the catalog with no login (Anonymous tier). The UCP CLI stays on Anonymous for Channel3 — it cannot send API keys. For production, use curl or an MCP client you control and add a Channel3 API key for the Token tier: higher rate limits and affiliate monetization on variants[].url buy links in catalog results (see Extension reference).

​
1. Create a key

  1. Go to the dashboard.
  2. Create an API key.
  3. Keep it out of git:
export CHANNEL3_API_KEY="ch3_live_..."

​
2. Send it on every MCP request

Add x-api-key to each POST to /mcp: 
# Anonymous only on Channel3 — no API key support in ucp-cli.
ucp catalog search \
  --set /query='wireless headphones' \
  --set '/pagination/limit=3' \
  --format json

​
3. Check that it worked

Response headers: 
x-ucp-auth-tier: token
In structuredContent, variant url values should use your vendor id in the buy.trychannel3.com path (not public_ucp). Compare with the same search without a key. Bad or missing keys fall back to anonymous limits (no 401): 
x-ucp-auth-tier: anonymous

​
What’s next

Rate limits

Anonymous vs Token

Search

Run a search with your key