Add a Perplexity API Key to Hermes Agent

What Is Perplexity?

Perplexity is an AI search company whose models — collectively called Sonar — combine a large language model with a live web search layer. Instead of answering from training data alone, Sonar retrieves current web pages, synthesises them, and returns a response alongside numbered citations linking to the source documents. This makes it particularly valuable for research, fact-checking, and any task that requires up-to-date information.

Perplexity is a pay-as-you-go provider: you are billed per million tokens at $1 per 1M input tokens and $1 per 1M output tokens for the Sonar model. There is no meaningful free tier, so you will need to add a payment method to your Perplexity account before generating an API key.

What Your Perplexity Key Unlocks in Hermes Agent

After saving a Perplexity key on the API Keys page, the following model becomes available as the primary model for your Hermes Agent instances:

• Sonar (sonar) — Perplexity's fast web-connected model. Searches the live web on every request, returns a synthesised answer, and appends numbered citations to original sources. Priced at $1 / 1M input tokens and $1 / 1M output tokens.

Sonar is the best choice for Hermes Agent deployments that need current events, real-time prices, recent documentation, or any information that changes faster than a model's training cutoff.

How to Get a Perplexity API Key

1. Go to the Perplexity API settings — Visit perplexity.ai/settings/api. Sign up for a Perplexity account if you don't have one.
2. Add a payment method — Perplexity requires a credit card before issuing API keys. Navigate to the Billing section and add your card.
3. Generate an API key — Under the API Keys section, click Generate, give the key a name (e.g. “Hermes Agent”), and confirm.
4. Copy the key — Your key starts with pplx-followed by a long alphanumeric string. Copy it immediately; Perplexity may not show the full key again after you navigate away.

Add Your Perplexity Key to Hermes Agent on OpenClaw Launch

1. Sign in at openclawlaunch.com and open the API Keys page.
2. Find the Perplexity card, paste your pplx- key, and click Save. OpenClaw validates the key live against the Perplexity API before encrypting and storing it.
3. After saving, click “Set as primary model” and select Sonar. The change pushes to all running Hermes Agent instances without a container restart.
4. Your key is stored encrypted at rest and never logged or exposed in plaintext.

Using OpenClaw (not Hermes Agent)? See the Perplexity for OpenClaw guide for the OpenClaw-specific walkthrough.

Troubleshooting

401 Unauthorized — Invalid API Key

• Confirm your key starts with pplx-. Keys copied from the wrong section of the Perplexity dashboard will fail this check.
• Check for invisible leading or trailing whitespace. Paste the key into a plain-text editor first, then copy it cleanly before entering it on the API Keys page.
• If you deleted the key and created a new one, the old value is permanently invalid. Update the entry on the API Keys page.

Model Not Found

• Use the exact model ID sonar (lowercase). Other Perplexity model names are not currently exposed through OpenClaw Launch.
• If Perplexity releases a new Sonar variant, check the API Keys page for an updated model list before entering a model ID manually.

Rate Limit or Billing Issue

• Perplexity uses per-minute rate limits tied to your account tier. If you see 429 errors, wait a moment and retry, or raise your rate limit in the Perplexity dashboard.
• Ensure your Perplexity account has a valid payment method and sufficient credit. A lapsed or declined card will cause all API calls to fail with an auth or billing error.
• Check instance logs in OpenClaw Launch — Sonar errors surface there with the exact status code and message from the Perplexity API.

Frequently Asked Questions

Is Perplexity free to use with Hermes Agent?

Perplexity is a pay-as-you-go service. The Sonar model is priced at $1 per 1M input tokens and $1 per 1M output tokens. There is no meaningful free tier, so you need to add a payment method at perplexity.ai/settings/api before generating a key.

What does a Perplexity API key look like?

Every Perplexity API key starts with pplx- followed by a long alphanumeric string. If your key doesn't match this pattern, you likely copied the wrong credential from the Perplexity dashboard.

Does Sonar search the web on every message?

Yes. Sonar performs a live web search for every request and includes citations in its response. This makes it ideal for time-sensitive queries but slightly slower than a pure LLM call. The citations are numbered references that Hermes Agent can surface to the user.

Will adding a Perplexity key restart my Hermes Agent containers?

No. Saving the key on the API Keys page and clicking “Set as primary model” hot-applies the change to running Hermes Agent instances without a container restart or any downtime.

What's Next?

• Perplexity for OpenClaw — The same Sonar web-search setup for OpenClaw instances
• Hermes Agent BYOK overview — Full guide to bringing your own keys across all providers for Hermes Agent
• Groq for Hermes Agent — Ultra-fast Llama and Kimi inference as an alternative to Sonar
• API Keys page — Add or update your Perplexity key right now