Web search providers
Configure Tavily, Perplexity, or Linkup as the backend for the web_search tool. Per-workflow + per-agent.
Cerevisor's web_search tool needs a backend. Three are supported:
| Provider | Strengths |
|---|---|
| Tavily | Built for LLM agents. Clean JSON, source URLs, decent recency. |
| Perplexity | Synthesized answers + sources. Often more analytical. |
| Linkup | Strong recency + European source coverage. |
License gate: Trial+/Paid only.
Configuration
Settings → Web Search lists every provider. For each:
| Field | What it does |
|---|---|
| API key | Paste your key, then Save key. Stored in the OS keychain. Clear removes it. |
| Test | Sends a trivial ping query without saving the key first, so you can validate before committing. |
The Active provider selector at the top of the tab picks the workflow-wide default: Disabled / Tavily / Perplexity / Linkup.
Per-agent overrides
In an Agent Config popup, the Search Provider field picks an override:
- Default: use the workflow's active provider.
- Tavily / Perplexity / Linkup: use this provider for this agent.
To turn web search off, set the workflow's active provider to Disabled — there's no per-agent off switch.
Useful when a workflow uses one provider broadly but a specific agent needs a different one (e.g. Linkup for EU-source coverage on one researcher agent).
Getting an API key
- Tavily: tavily.com: sign up, generate key from dashboard.
- Perplexity: perplexity.ai/settings/api: requires Pro subscription for API access.
- Linkup: linkup.so: sign up, generate key.
Test before saving
The Test button on each provider runs a minimal smoke test:
- Sends
query: 'ping'with a 10-second timeout. - Returns
{ ok: true/false, message, status? }. - Uses a redactor so your API key never appears in error messages.
If the test fails:
401/403: invalid key.429: rate limited or quota exhausted.Network timeout: provider unreachable, or you don't have internet.
How the web_search tool calls the provider
When an agent calls web_search, Cerevisor:
- Resolves the agent's search provider (per-agent override → workflow active provider).
- If nothing usable is configured, the tool returns a "not configured" error to the agent.
- Otherwise, calls the provider's search API.
- Returns the structured results to the agent: title, URL, snippet, publish date (when available).
The agent processes the results in its own loop, typically following up with web_fetch calls on URLs it wants to read in full.
Cost
Each provider bills per API call (sometimes per result returned). Cerevisor doesn't track web-search cost in its run cost display: the cost lives on your provider's dashboard.
For heavy research workflows, Linkup is often the cheapest at scale; Perplexity is more expensive but produces richer output.
When you don't have a search provider
The web_search tool fails gracefully, returns an error to the agent. Agents that explicitly list web_search in their allowed tools also trigger a pre-run warning when no provider (or no key) is configured, so you'll know before the run — the run still starts.
For workflows that don't need web search, set the active provider to Disabled and skip configuration.
Adding a new backend
Adding a new web-search provider to Cerevisor is a small change in the codebase: a new entry in the search-provider registry, a new probe function, a new dispatch branch in the web_search tool. If a provider you use isn't in the list, it's a one-PR addition.