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Model infoModelsSnapshot: 15 Oct 2026

Inflection AI / Pi proprietary adaptations

Pi 3.1 Preview

Historical beta adaptation of a Llama base, trained for conversational personality and tool use.

Language models (LLMs)
historicalClosed weightsText generation
Official documentation (opens in a new tab)Reviewed 14 Oct 2026
5 of 17 specification fields collected
Context windowNot collectedAwaiting source review
Maximum outputNot collectedAwaiting source review
Input billingNot collectedInflection API (historical preview)
Output billingNot collectedNo inferred price

Specifications

Provider-documented facts. “Not collected” means we have not verified that field yet, not that the feature is unsupported.

Context / input limit
Not collected
Maximum output
Not collected
Input modalities
TextSource for Input modalities (opens in a new tab)
Output modalities
TextSource for Output modalities (opens in a new tab)
Reasoning
Not collected
Tool calling
SupportedSource for Tool calling (opens in a new tab)

Explicitly documented for the 3.1 preview; not copied to the 3.0 variants.

Structured output
Not collected
Streaming
Not collected
Batch processing
Not collected
Fine-tuning
Not collected
Knowledge cutoff
Not collected
Release date
Not collected
Parameters
Not collected
Architecture
Fine-tuned from a Llama base; exact base version and parameter count unverifiedSource for Architecture (opens in a new tab)
Languages
Not collected
Context caching
Not collected
lastDocumentedStage
Beta preview for agentic workflowsSource for lastDocumentedStage (opens in a new tab)

Stage in the November 2025 archive; current availability unverified.

Access & pricing

Prices belong to an endpoint and billing tier. A provider listing does not guarantee access for every account or region.

Inflection API (historical preview)

Provider source (opens in a new tab)
API model ID
Pi-3.1
Access
Archived preview selector with tool calling. Current portal, model availability, limits and prices are unverified.
Regions
Current regional availability unverified.

Endpoint pricing has not been collected. Check the provider for applicable rates.

Data & enterprise terms

Retention, training use, regional processing and enterprise terms have not been summarized for this endpoint.

Caching

Caching can reuse earlier input processing. Availability, lifetime and billing depend on the endpoint. A cache hit still generates a new response.

01 / INITIAL INPUTProcess & retain

The system processes eligible input and retains reusable state.

02 / LATER REQUESTCheck available state

Reuse depends on matching input, session state and the cache policy.

03 / CACHE HITReuse & generate

Reusing state can reduce repeated work. Any charges follow the billing rules below.

Inflection API (historical preview)

Pi-3.1
Not verified

No model-specific cache contract verified.

How it works
Not collected

No model-specific cache contract verified.

Minimum reusable input
Not collected

No model-specific cache contract verified.

Lifetime & refresh
Not collected

No model-specific cache contract verified.

How to enable it
Not collected

No model-specific cache contract verified.

Usage fields
Not collected

No model-specific cache contract verified.

Billing rules
Not collected

No model-specific cache contract verified.

Limits & data boundaries
Not collected

No model-specific cache contract verified.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

What the measurements say

No benchmark observations have been added for this model. We do not turn a vendor description into a performance score.

Latency and throughput depend on the host, request size, reasoning settings and load. There is no measured speed or global usage figure in this record.

The record behind the model

Why it is included

Inferred from the developer’s in-house model or proprietary API adaptation description and restricted access. The reviewed release supplies no weights for this exact checkpoint; this does not classify its dependencies or openly released base models as closed.

Classification evidence (opens in a new tab)

Sources reviewed