CISO Tribune

Vendor comparison · 2 companies

Fiddler AI vs Harmonic Security

Fiddler AI sells the AI Control Plane, a platform for first-party and third-party agents from the creation layer to production. Harmonic Security sells AI Governance and Control (AIGC), a control layer that secures and enables the AI-First workforce. CISO Tribune files both under AI model and agent security and AI governance. 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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  • Fiddler AI
  • Harmonic Security
Fiddler AI vs Harmonic Security: Products, Customers and Funding Compared
Fiddler AIFiddler AI sells the AI Control Plane, a platform for first-party and third-party agents from the creation layer to production.fiddler.aiHarmonic SecurityHarmonic Security sells AI Governance and Control (AIGC), a control layer that secures and enables the AI-First workforce.harmonic.security
What it sells
  • Agentic Observability[2][4]Monitors every layer of the agentic hierarchy, from application health to agent interactions to individual spans.
  • ML Observability[2][5]Detects data and concept drift in predictive models and provides root cause analysis and fairness metrics.
  • Fiddler Centor Models[2][3][6]Power guardrails and evaluations in-environment, with no external LLM API calls.
  • Agent Registry[7]Lists every agent application in Fiddler, including first-party, third-party and coding agents.
  • Harmonic Command[3]Gives security teams visibility into how employees and agents use AI, plus controls for using the tools safely.
  • MCP Gateway[2][3][4][6]A local gateway that extends Harmonic coverage to MCP activity.
  • Harmonic Endpoint Agent[6]Identifies native AI apps, IDEs, CLI tools, locally hosted models and inference API calls on employee devices.
  • Harmonic Usage Intelligence[8]Groups prompts, files, responses, and supported agent actions into tasks and use cases.
Categories
Headquarters
Not stated on its pagesNot stated on its pages
Founded
2018[1]Not stated on its pages
Ownership and funding
Privately held[12]Privately held
Named customers
Not stated on its pagesNot stated on its pages
Recent news
  • January 27, 2026Fiddler AI announced a $30 million Series C funding round led by RPS Ventures.[1]
Not stated on its pages
G2 and Gartner Peer Insights
  • G2: listed, seen November 10, 2026[12]
  • 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
From its own pages, Fiddler AI sells mainly to organizations deploying AI agents and predictive models, across all industries and in regulated industries such as financial services, healthcare, insurance and government. The typical users are software and AI engineers, data scientists, platform and DevOps teams, and security and compliance teams. Its pages address insurers, healthcare organizations and financial institutions deploying AI across underwriting, fraud and trading. Deployment options on the Enterprise plan are SaaS, VPC or on-premises.Not written yet
Last verified
November 6, 2026November 3, 2026

Where they overlap

  • Fiddler AI and Harmonic Security are both filed under AI model and agent security and AI governance.
  • Both are privately held.

Where they differ, field by field

  • Fiddler AI's primary category is AI model and agent security; Harmonic Security's is Workforce AI usage security.
  • Fiddler AI is also filed under AI firewalls and guardrails. Harmonic Security is also filed under Data loss prevention.
  • Fiddler AI lists Agentic Observability, ML Observability, Fiddler Centor Models and Agent Registry. Harmonic Security lists Harmonic Command, MCP Gateway, Harmonic Endpoint Agent and Harmonic Usage Intelligence.
  • Fiddler AI was founded in 2018.

What it sells: Fiddler AI

What Agentic Observability does[2][4]
Fiddler Agentic Observability monitors every layer of the agentic hierarchy from application health to agent interactions to individual spans. Fiddler gives aggregated and granular visibility from application to session to agent to trace to span.
What ML Observability does[2][5]
Fiddler ML Observability provides root cause analysis and fairness metrics such as disparate impact, demographic parity and equal opportunity. Fiddler tracks performance, drift, data integrity and model bias to observe and improve model health.
What Fiddler Centor Models does[2][3][6]
Fiddler Centor Models power guardrails and evaluations in-environment, with no external LLM API calls. Customers can choose Fiddler Centor Models that run in their environment, custom evaluators for domain-specific logic, or external judges for advanced reasoning.
What Agent Registry does[7]
Agent Registry lists every agent application in Fiddler, including first-party, third-party and coding agents. Fiddler records evaluation and policy outcomes with full traceability and generates audit evidence aligned with frameworks such as GDPR, HIPAA, NAIC, SR 11-7, NIST AI RMF, ISO/IEC 42001 and the EU AI Act.

What it sells: Harmonic Security

What Harmonic Command does[3]
Harmonic Command covers workforce AI use across supported browsers, desktop applications, command-line tools, AI APIs, and agentic workflows that use MCP. Harmonic Command intercepts the action and guides the user or agent toward a safer path.
What MCP Gateway does[2][3][4][6]
Supported OpenTelemetry sources and the local MCP Gateway extend Harmonic coverage to additional native, command-line, and MCP activity. The Harmonic MCP Gateway pairs with the Endpoint Agent and applies to agentic workflows. The MCP Gateway runs on Windows, macOS, and Linux.
What Harmonic Endpoint Agent does[6]
The Harmonic Endpoint Agent detects Claude Desktop, Claude Code, Claude Cowork and OpenAI Codex on macOS and Windows. The Endpoint Agent identifies locally hosted models such as Ollama on employee devices and ties that activity to the process and user behind it. Harmonic identifies connections to inference endpoints like OpenAI, Anthropic, Bedrock and Azure AI Foundry.

Questions about Fiddler AI and Harmonic Security

What do Fiddler AI and Harmonic Security sell?
Fiddler AI sells Agentic Observability, ML Observability, Fiddler Centor Models and Agent Registry. Harmonic Security sells Harmonic Command, MCP Gateway, Harmonic Endpoint Agent and Harmonic Usage Intelligence.
Are Fiddler AI and Harmonic Security in the same category?
They share AI model and agent security and AI governance. Fiddler AI's primary category is AI model and agent security and Harmonic Security's is Workforce AI usage security.
When were Fiddler AI and Harmonic Security founded?
Fiddler AI was founded in 2018.
Who owns Fiddler AI and Harmonic Security?
Fiddler AI is privately held. Harmonic Security is privately held.
Who are Fiddler AI and Harmonic Security sold to?
From its own pages, Fiddler AI sells mainly to organizations deploying AI agents and predictive models, across all industries and in regulated industries such as financial services, healthcare, insurance and government.
What have Fiddler AI and Harmonic Security announced recently?
January 27, 2026: Fiddler AI announced a $30 million Series C funding round led by RPS Ventures.

About Fiddler AI

Fiddler AI sells the AI Control Plane, a platform for first-party and third-party agents from the creation layer to production. Fiddler combines continuous evaluation, monitoring, enforceable policy and auditable governance for enterprises. Fiddler Centor Models power guardrails and evaluations in-environment, with no external LLM API calls.[2][3]

Fiddler Agentic Observability monitors every layer of the agentic hierarchy from application health to agent interactions to individual spans. Fiddler ML Observability provides root cause analysis and fairness metrics such as disparate impact, demographic parity and equal opportunity. Fiddler Guardrails enforce policy inline, at the agent's request and response path, in under 80ms. Fiddler detects and redacts PII, PHI and secrets on the same request, before a prompt reaches the model and before a response reaches the developer. The Free plan includes real-time guardrails powered by Fiddler Centor Models at under 80ms latency, protecting against hallucinations, toxicity, PII/PHI, prompt injection and jailbreak attempts. Fiddler tracks 100+ out-of-the-box and custom metrics including hallucination, toxicity, PII/PHI leakage and jailbreak attempts.[2][3][4][5][6]

Fiddler AI provides centralized governance and oversight for agents and predictive models across the enterprise, with a registry of your agents, enforced guardrails and the audit evidence needed to meet evolving regulatory requirements. Agent Registry lists every agent application in Fiddler, including first-party, third-party and coding agents. Fiddler records evaluation and policy outcomes with full traceability and generates audit evidence aligned with frameworks and regulations such as GDPR, HIPAA, NAIC, SR 11-7, NIST AI RMF, ISO/IEC 42001 and the EU AI Act. Guardrails run in your own environment, so prompts and responses never leave your infrastructure. Teams can monitor predictive models and agents for drift, bias and performance degradation, run deep diagnostics to find root causes, and create custom reports for MRM and compliance reviews. Fiddler extends governance to the creation layer, monitoring the IDE, CLI and MCP boundary to validate tool invocations against allowlists, scan for secrets, and prevent coding agents from committing insecure code or accessing unauthorized repositories.[5][7]

Fiddler is offered in SaaS, VPC and AWS GovCloud. Fiddler can be deployed in any secure cloud environment or air-gapped. Fiddler states it is SOC 2 Type II compliant, with role-based access control and SSO. Fiddler states it is HIPAA ready. Fiddler AI Observability can run within Amazon SageMaker Studio. Fiddler is model- and cloud-agnostic, working across Azure OpenAI, Amazon Bedrock, LangGraph and 100+ other providers. The Developer plan is usage-based at $0.002 per trace and adds unified observability for agentic and predictive systems, custom evaluators and SSO. The Enterprise plan adds flexible deployment of SaaS, VPC or on-premises, along with white-glove support with a named Customer Success Manager and customized onboarding.[3][5][8]

Fiddler AI is used by organizations deploying agents across all industries, as well as highly regulated industries like financial services, healthcare, insurance and government. The typical users are software and AI engineers, data scientists, platform and DevOps teams, and security and compliance teams. Fiddler positions its AI Observability and Security platform as the Unified AI Command Center for insurers. Fiddler provides a unified AI observability and security platform for healthcare organizations. Fiddler describes itself as the control plane for AI agents in financial services, covering monitoring, policy and governance. Financial institutions deploying AI across underwriting, fraud and trading rely on Fiddler for unified observability, policy enforcement and regulatory-ready audit trails. Fiddler monitors Natural Language Processing and Computer Vision models to track and get real-time alerts on anomalies and data drift. Fiddler explains predictions in ML models powering autonomous vehicles, such as aerial drones and unmanned underwater vehicles. Fortune 100 organizations use Fiddler for agentic and predictive applications. For customer-facing agents, Fiddler governs agents built in-house or integrated from third-party providers in a unified dashboard with audit evidence for GDPR, CCPA, HIPAA and NAIC compliance.[2][3][4][5][6][8][9][10]

Fiddler's founders began with explainability and then expanded to observability to track how models change over time. Fiddler describes itself today as the Control Plane for AI Agents. IQT first invested in Fiddler in 2019.[2][4][6][8][10][11]

Fiddler AI on the record

Sources

Fiddler AI full record

  1. [1]Fiddler Raises $30M Series C to Deliver the First Control Plane for AIFiddler AI · published January 27, 2026 · Tier A
  2. [2]fiddler.aiFiddler AI · fiddler.ai · undated page, accessed November 6, 2026 · Tier A
  3. [3]Fiddler AI: The Control Plane for Enterprise AI AgentsFiddler AI · undated page, accessed November 10, 2026 · Tier A
  4. [4]Fiddler AI Observability for Healthcare LLM ApplicationsFiddler AI · undated page, accessed November 10, 2026 · Tier A
  5. [5]Fiddler AI Control Plane for Financial Services | Fiddler AIFiddler AI · undated page, accessed November 10, 2026 · Tier A
  6. [6]Customer Experience AI Observability for Agents | Fiddler AIFiddler AI · undated page, accessed November 10, 2026 · Tier A
  7. [7]AI Governance, Risk Management, and Compliance (GRC) | Fiddler AIFiddler AI · undated page, accessed November 10, 2026 · Tier A
  8. [8]Fiddler AI Observability for Insurance LLM Applications | Fiddler AIFiddler AI · undated page, accessed November 10, 2026 · Tier A
  9. [9]AI Observability for Lending and Trading | Fiddler AIFiddler AI · undated page, accessed November 10, 2026 · Tier A
  10. [10]Government | Fiddler AIFiddler AI · undated page, accessed November 10, 2026 · Tier A
  11. [11]About Us | Fiddler AIFiddler AI · undated page, accessed November 10, 2026 · Tier A
  12. [12]Fiddler AI Reviews 2026: Details, Pricing, & FeaturesG2 · undated page, accessed November 10, 2026 · Tier C

Harmonic Security full record

  1. [1]Harmonic Security | AI Security for the WorkforceHarmonic Security · undated page, accessed November 3, 2026 · Tier A
  2. [2]Harmonic Security Raises $50 Million Series B Enabling Safe AI Adoption for Millions More EmployeesBusiness Wire · businesswire.com · published October 14, 2026 · Tier A
  3. [3]Harmonic Command: AI Governance & Usage Intelligence Platform | Harmonic SecurityHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  4. [4]Harmonic Explore: AI Usage Visibility & Shadow AI Discovery | Harmonic SecurityHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  5. [5]Harmonic Guide: Real-Time AI Policy Enforcement & Inline Controls | Harmonic SecurityHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  6. [6]Endpoint AI Security & ControlHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  7. [7]Browser-Based GenAI SecurityHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  8. [8]AI Usage IntelligenceHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  9. [9]AI Usage Governance: Enterprise AI Policy & ControlHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  10. [10]DLP for Generative AIHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  11. [11]GenAI Compliance for Regulated IndustriesHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  12. [12]AI Security for HealthcareHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  13. [13]AI Security for InsuranceHarmonic Security · undated page, accessed November 10, 2026 · Tier A

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