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Hermes vs OpenAI Realtime API
Hermes is positioned as an agency operations layer bundling voice providers, client workspaces and billing. OpenAI Realtime API is positioned as speech-to-speech API for developers implementing their own voice application. Start b
Hermes is positioned as an agency operations layer bundling voice providers, client workspaces and billing. OpenAI Realtime API is positioned as speech-to-speech API for developers implementing their own voice application. Start by deciding who owns the missing layers, then inspect the documented differences below.
Full Platforms and Developer Frameworks are different product categories. An underlying engine or framework is not a complete substitute for a deployed agent workflow.
5 jointly documented catalog fields. This measures evidence coverage, not equivalent quality or an overall winner.
Test opening hours, booking conflicts and an unanswered transfer.
Start where the records differ.
Values and evidence states are compared together. Shared facts follow the differences; Unknown never means No.
| Decision point | Hermes | OpenAI Realtime API |
|---|---|---|
| Billing modelDifferent records | monthly-bundle | component-stack |
| Billing unitDifferent records | month | 1 million text/audio/image tokens; transcription separately metered |
| Bring your telephonyDifferent records | Unknown | Yes |
| WebhooksDifferent records | YesAPI / webhook | YesUnknown |
| Bring your modelShared state | Unknown | Unknown |
| Warm transferShared state | Unknown | Unknown |
Your requirements & next steps
Your requirements
Ready-made / AI receptionist · Strict evidence mode
No personal requirements yet. Add criteria in Advanced Filter to prioritize this comparison.
Reviewed current public offer; retain original billing scope and units.
Realtime model tokens plus input transcription, tools and carrier/hosting; not GPT-Live session-minute billing.
Reviewed current public offer; retain original billing scope and units.
Cached audio/text and image inputs have separate rates. Rate is not per-minute.
Reviewed current public offer; retain original billing scope and units.
Model scope fixed to GPT-Realtime-2, not all voice models.
Reviewed current public offer; retain original billing scope and units.
Published Realtime token rates do not establish these account/contract terms. GPT-Live duration billing and unrelated fine-tuning discounts must not be imported.
Reviewed current public offer; retain original billing scope and units.
Published Realtime token rates do not establish these account/contract terms. GPT-Live duration billing and unrelated fine-tuning discounts must not be imported.
Official overage rates conflict, messaging pass-through varies and beta account terms need confirmation.
Published Realtime token rates do not establish these account/contract terms. GPT-Live duration billing and unrelated fine-tuning discounts must not be imported.
Reviewed current public offer; retain original billing scope and units.
Repeated context, cache behavior and turn count affect token charges.
Official overage rates conflict, messaging pass-through varies and beta account terms need confirmation.
Not yet researched against this buyer-critical field standard.
Official overage rates conflict, messaging pass-through varies and beta account terms need confirmation.
Full bill requires measured model/token/cache/tool/carrier usage; conversation minutes alone are insufficient.
Research conclusion about cost completeness, not a vendor capability.
Full bill requires measured model/token/cache/tool/carrier usage; conversation minutes alone are insufficient.
Anyone with this link can view the encoded decision criteria.
Vendor documentation establishes a claim. Public model benchmarks are separate context, not measurements of these platforms.
Open saved comparison ↗What to verify together.
Hermes
The service is advertised as a private beta with public launch pending.
Starter $149/month · V3.3 evidence review · Starter private beta subscription; unresolved overage scope
Excluded / confirm: Complete cost cannot be established from this reference. Official overage rates conflict, messaging pass-through varies and beta account terms need confirmation. · A2P messaging pass-through and customer billing configuration vary
Reviewed current public offer; retain original billing scope and units.
OpenAI Realtime API
A token rate cannot be compared directly with a bundled call-minute price.
GPT-Realtime-2 audio input $32/M, audio output $64/M; text input $4/M, output $24/M · V3.3 evidence review · GPT-Realtime-2 input audio tokens only; output/audio/text/cache have different rates; not 2.1 rate evidence
Excluded / confirm: Complete cost cannot be established from this reference. Full bill requires measured model/token/cache/tool/carrier usage; conversation minutes alone are insufficient. · Input transcription, tool/backend calls, carrier and application infrastructure
Realtime model tokens plus input transcription, tools and carrier/hosting; not GPT-Live session-minute billing.
The evidence overlap.
Both records have documented values for Product type, Pricing model, Published numeric pricing, Checked within 30 days, Retained price snapshot. Matching availability does not measure behavior under your call conditions.
Run the same booking, tool failure and unsuccessful human-transfer cases. Record both outcomes and billable units before signing a deployment agreement.
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