Comparison
PromptCache vs Portkey
Portkey describes itself as an AI gateway with prompt management and routing built in; PromptCache does not route model traffic and focuses on the prompt store itself.
Verified against Portkey’s public documentation on
Portkey describes itself as an AI gateway with prompt management and routing built in. PromptCache is a prompt store that does not route model traffic. That difference in category matters more than any feature in the table below.
Feature comparison
| PromptCache | Portkey | |
|---|---|---|
| Product category | Prompt store | AI gateway with prompt management |
| Prompt versioning | Numbered versions created by publishing | Automatic new version on each modification |
| Draft vs published | Draft, then publish to create a version | Update saves locally; publish marks the production default |
| Version addressing | Environment slot resolves a version | @12, @latest, or label such as @production |
| Labels | Preview and production slots | Production, staging, development defaults plus unlimited custom labels |
| Multiple labels per version | One slot points at one version | A version can carry multiple labels |
| Version history | Timeline with diff between any two versions | History, restore, side-by-side comparison |
| Gateway routing | Not offered | Core product capability |
| Provider failover | Not offered | Core product capability |
| Proxies your model calls | No | Yes, the gateway is the product |
| MCP server | Yes, remote MCP over OAuth 2.1 + PKCE | Not documented |
| Public prompt gallery | Yes, with forking | Not documented |
Both products separate saving a change from making it live, Portkey distinguishes updating from publishing, PromptCache distinguishes publishing a version from pointing an environment slot at it. The mechanics differ; the safety property is the same.
Where Portkey is the better choice
You need routing and failover. This is the real reason to choose Portkey. If calls should fail over between providers, or you want one interface across several model vendors, that is the product's core competence and PromptCache offers nothing comparable.
You want richer label semantics. Portkey documents unlimited custom labels and multiple labels per version. PromptCache has two fixed slots, preview and production. For teams running more than two environments, Portkey's model is more flexible.
You want version addressing options in code. Referencing @12, @latest, or @production from the same call site is convenient when different callers need different resolution behaviour.
You are already routing through a gateway. Adding a separate prompt store when your gateway already manages prompts is redundancy without much return.
Where PromptCache differs
No proxy. PromptCache returns the rendered template; your application calls the model itself. Portkey's value depends on your traffic flowing through it. If you do not want a vendor in the completion path, that is disqualifying regardless of the prompt features.
Fewer moving parts. A gateway is infrastructure, another hop, another failure mode, another thing to reason about during an incident. If prompts are the only problem you have, a prompt store is a smaller commitment.
Assistant and workflow integration. The remote MCP server over OAuth 2.1 and PKCE, plus a read-only n8n community node, have no documented equivalent in Portkey's prompt versioning documentation.
Choosing between them
The question is not which has better prompt versioning, both are competent, and Portkey's labelling is more flexible. The question is whether you want an AI gateway.
If yes, use Portkey's prompt management and skip the separate store. If no, a gateway is a large dependency to adopt for prompt features you can get without it.
Honest limitations
Paid plans are invoiced manually, with no self-serve checkout. Portkey's prompt versioning is available across all its pricing tiers, and as a product it is broader and more established.
Sources
Where Portkey's documentation does not address a capability, this page records it as "not documented" rather than asserting absence.
Frequently asked questions
- Is Portkey a prompt manager or an AI gateway?
- Portkey describes itself as an AI gateway with prompt management and routing built in. PromptCache is a prompt store and does not route model traffic. That difference in category matters more than any individual feature.
- Can one prompt version carry several labels?
- In Portkey, yes: it documents production, staging, and development defaults plus unlimited custom labels, and a version can carry more than one. In PromptCache, one environment slot points at one version.
- How is a specific version addressed at runtime?
- Portkey documents addressing a version number, latest, or a label such as production. PromptCache resolves the version an environment slot currently points at.
- Does PromptCache offer provider failover?
- No. Routing and failover between model providers are core Portkey capabilities and PromptCache offers nothing comparable. If calls should fail over between providers, that decides it.