CISO Tribune

Vendor comparison · 2 companies

Impart Security vs Promptfoo

Impart Security sells programmable, deterministic Layer 7 protection across AI, applications and APIs. Promptfoo builds open-source tools for secure, reliable AI applications. CISO Tribune files both under AI firewalls and guardrails and AI model and agent security. This page sets the two records side by side: what each sells, where it is based, who owns and funds it, the customers it names and its recent news, each fact numbered to its source.

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  • Impart Security
  • Promptfoo
Impart Security vs Promptfoo: Products, Customers and Funding Compared
Impart SecurityImpart Security sells programmable, deterministic Layer 7 protection across AI, applications and APIs.impart.aiPromptfooPromptfoo builds open-source tools for secure, reliable AI applications.promptfoo.dev
What it sells
  • Agent Protection[3][10]Enforces application-specific policies on agent traffic and tool interactions.
  • API Security[5][8][10]Enforces controls based on how APIs behave across requests and sessions.
  • Runtime Defense Harness[10]Uses AI-assisted investigation to develop targeted virtual patches.
  • Red Teaming[2][4][5]Simulates real users to uncover application-specific vulnerabilities.
  • Evaluations[2][5]LLM evaluation of prompts and models that can run inside CI workflows.
Categories
Headquarters
San Francisco, United StatesSan Francisco, United States[1][3]
Founded
Not stated on its pages2024[1][12]
Ownership and funding
Privately heldOwned by OpenAI[12]
Named customers
Not stated on its pagesNot stated on its pages
Recent news
Not stated on its pages
  • March 9, 2026OpenAI agreed to buy Promptfoo, a startup helping businesses find and fix security issues in AI models during development.[13]
  • March 9, 2026OpenAI announced it has acquired Promptfoo, an AI security startup founded in 2024 to protect LLMs from adversarial attacks.[12]
G2 and Gartner Peer Insights
  • G2: Not stated on its pages
  • Gartner Peer Insights: Not stated on its pages
  • G2: Not stated on its pages
  • Gartner Peer Insights: Not stated on its pages
Who it fits
Impart describes protection that runs inside an organisation's existing ingress. The stated coverage spans AI, applications and APIs. Impart also describes integrating its protection into existing ingress and egress infrastructure, with policies and runtime state synchronized across distributed environments.Not written yet
Last verified
September 27, 2026November 4, 2026

Where they overlap

  • Impart Security and Promptfoo are both filed under AI firewalls and guardrails and AI model and agent security.
  • Both are headquartered in San Francisco, United States.

Where they differ, field by field

  • Impart Security's primary category is AI firewalls and guardrails; Promptfoo's is AI model and agent security.
  • Impart Security is also filed under Bot and abuse management. Promptfoo is also filed under Static application security testing and Breach simulation and automated pen-testing.
  • Impart Security lists Agent Protection, API Security and Runtime Defense Harness. Promptfoo lists Red Teaming and Evaluations.
  • Promptfoo was founded in 2024.
  • Impart Security is privately held. Promptfoo is owned by OpenAI.

What it sells: Impart Security

What Agent Protection does[3][10]
Agent Protection enforces application-specific policies on agent traffic and tool interactions, using runtime context to restrict unauthorized actions and access. Agent Protection runs on the same ingress-layer enforcement engine that inspects the full attack surface.
What API Security does[5][8][10]
API Security enforces controls based on how APIs behave across requests and sessions, not just individual request signatures. Impart applies inline, sequence-aware enforcement to every API call. API Security detects and blocks shadow APIs as they are accessed. API Security prevents sensitive data (PII) from leaving the system.
What Runtime Defense Harness does[10]
Runtime Defense Harness uses AI-assisted investigation to develop targeted virtual patches and deploy protection through the same engine already protecting the applications. Targeted virtual patches are generated and tested against runtime traffic, with Policy as Code validated before deployment. AI-generated virtual patches are informed by runtime behavior, tested against live traffic and enforced through programmable Layer 7 controls.

What it sells: Promptfoo

What Red Teaming does[2][4][5]
Promptfoo creates thousands of context-aware attacks tailored to the customer's application. The open-source Community version includes up to 10k probes per month at no charge.
What Evaluations does[2][5]
Promptfoo's LLM evaluation can be integrated into a CircleCI pipeline. Promptfoo can be integrated with test frameworks like Jest and Vitest to evaluate prompts as part of existing testing and CI workflows. Promptfoo provides real-time alerts and automated evaluations to show LLM security status across all projects.

Questions about Impart Security and Promptfoo

What do Impart Security and Promptfoo sell?
Impart Security sells Agent Protection, API Security and Runtime Defense Harness. Promptfoo sells Red Teaming and Evaluations.
Are Impart Security and Promptfoo in the same category?
They share AI firewalls and guardrails and AI model and agent security. Impart Security's primary category is AI firewalls and guardrails and Promptfoo's is AI model and agent security.
Where are Impart Security and Promptfoo headquartered?
Both are headquartered in San Francisco, United States.
When were Impart Security and Promptfoo founded?
Promptfoo was founded in 2024.
Who owns Impart Security and Promptfoo?
Impart Security is privately held. Promptfoo is owned by OpenAI.
Who are Impart Security and Promptfoo sold to?
Impart describes protection that runs inside an organisation's existing ingress.
What have Impart Security and Promptfoo announced recently?
March 9, 2026: OpenAI agreed to buy Promptfoo, a startup helping businesses find and fix security issues in AI models during development.

About Impart Security

Impart Security sells programmable, deterministic Layer 7 protection across AI, applications and APIs. Impart enforces security policies directly in the application traffic path. Impart describes one programmable engine that unifies OWASP coverage, stateful behavioral analysis and custom security logic to block threats inline. Impart defines runtime enforcement as the ability to detect and block a threat at the moment the request is made, inline in the path of live traffic. Impart integrates programmable Layer 7 protection into existing ingress and egress infrastructure, enforces deterministic controls locally, and synchronizes policies and runtime state across distributed environments.[4][6][9][10]

For bots, Impart blocks credential stuffing, scraping and AI-driven automation with stateful controls that evaluate request patterns and session behavior. For agents, Impart enforces application-specific policies on agent traffic and tool interactions, using runtime context to restrict unauthorized actions and access. Impart detects and blocks shadow APIs as they are accessed. Impart's API enforcement prevents sensitive data (PII) from leaving the system.[8][10]

Impart sits between the agent and the customer's systems, enforcing security before any action executes. Agent protection runs on the same ingress-layer enforcement engine that inspects the full attack surface. Impart evaluates each prompt using session history, identity, prior model interactions and the chain of tool calls behind it. Impart's LLM enforcement sits inline between the caller and the model and runs before the prompt reaches inference. Impart builds a live catalog of every MCP server reaching the environment, sanctioned or not, and every tool exposed by each one. Policy-as-code in Impart applies the same way to AI clients, CLI users, web apps and direct API callers.[3][5][6][8]

Runtime Defense Harness uses AI-assisted investigation to develop targeted virtual patches and deploy protection through the same engine already protecting the applications. Impart generates and tests targeted virtual patches against runtime traffic, validating Policy as Code before deployment. Impart deploys custom virtual patches in under 60 minutes. Impart executes custom security logic inline using request context and shared session state, and blocks attacks without model inference in the traffic path.[4][10]

Impart runs inside the existing ingress, without adding an extra traffic hop or single point of failure. A lightweight module runs inside the existing ingress controller, capturing HTTP requests after TLS termination and passing them to a local inspector. If the inspector fails or times out, the module fails open. The Impart inspector runs locally alongside the ingress to evaluate request context, runtime state and custom security logic. Enforcement decisions in Impart are deterministic, and no AI inference or cloud round trip is required. Impart Cloud keeps policies and shared state in sync. Impart extends programmable Layer 7 protection to outbound AI requests and agent interactions through supported AI gateway infrastructure. Impart inspects traffic, applies custom security logic and protects sensitive data without replacing the existing gateway, routing or cost controls. The Impart Security plugin runs natively inside Kong Gateway, paired with an Impart Inspector running in the customer's own environment.[5][9][10]

Impart inspects every request to AI applications, web applications and APIs in the traffic path where it sits. The Impart integration with Wiz sends hosts to a Wiz tenant as Imported Assets, next to the cloud resources. Impart sends hostnames to Wiz and does not read Wiz issues, findings or resources. FanDuel replaced black-box security with Impart. Impart offered Crossbeam a single solution for web application, API security and LLM protection.[1][2][3][4][5][6][7][8][9][10]

Impart Security on the record

Sources

Impart Security full record

  1. [1]impart.aiImpart Security · impart.ai · undated page, accessed September 27, 2026 · Tier A
  2. [2]impart.aiImpart Security · impart.ai · undated page, accessed September 27, 2026 · Tier A
  3. [3]Agent Protection - Control AI Agent Behavior | ImpartImpart Security · undated page, accessed September 27, 2026 · Tier A
  4. [4]AI Runtime Defense | Impart Security PlatformImpart Security · undated page, accessed October 25, 2026 · Tier A
  5. [5]LLM Protection | Deterministic Agent Controls | ImpartImpart Security · undated page, accessed October 25, 2026 · Tier A
  6. [6]MCP Protection | Runtime Control for MCP Layer | ImpartImpart Security · undated page, accessed October 25, 2026 · Tier A
  7. [7]WAF for the Agentic Era | Impart SecurityImpart Security · undated page, accessed October 25, 2026 · Tier A
  8. [8]API Security for the Agentic Era | Impart SecurityImpart Security · undated page, accessed October 25, 2026 · Tier A
  9. [9]Integrations with Impart Security | Impart Security Runtime ProtectionImpart Security · undated page, accessed November 10, 2026 · Tier A
  10. [10]Programmable Layer 7 Firewall | Impart SecurityImpart Security · undated page, accessed November 10, 2026 · Tier A

Promptfoo full record

  1. [1]PressPromptfoo · promptfoo.dev · undated page, accessed November 4, 2026 · Tier A
  2. [2]promptfoo.devPromptfoo · promptfoo.dev · undated page, accessed November 4, 2026 · Tier A
  3. [3]About Promptfoo | AI Security Experts | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  4. [4]Build Secure AI Applications | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  5. [5]Pricing | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  6. [6]Setting up Promptfoo with CircleCI | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  7. [7]Testing prompts with Jest and Vitest | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  8. [8]Finding LLM Jailbreaks with Burp Suite | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  9. [9]SharePoint Integration | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  10. [10]Langfuse integration | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  11. [11]AI Security for Real Estate | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  12. [12]OpenAI acquires Promptfoo to secure its AI agents | TechCrunchTechCrunch · published March 9, 2026 · Tier B
  13. [13]OpenAI Buying AI Security Startup Promptfoo to Safeguard AI Agents - BloombergBloomberg · published March 9, 2026 · Tier B

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