In this comprehensive guide, we compare Glean and Vertex AI across various parameters including features, pricing, performance, and customer support to help you make the best decision for your business needs.
Overview
When choosing between Glean and Vertex AI, understanding their unique strengths and architectural differences is crucial for making an informed decision. Both platforms serve the RAG (Retrieval-Augmented Generation) space but cater to different use cases and organizational needs.
Quick Decision Guide
Choose Glean if: you value permissions-aware ai is genuinely differentiated - real-time enforcement across 100+ datasources addresses critical enterprise concern
Choose Vertex AI if: you value industry-leading 2m token context window with gemini models
About Glean
Glean is enterprise work ai with permissions-aware rag across 100+ apps. Glean is a premium enterprise RAG platform with permissions-aware AI as its core differentiator. Founded by ex-Google Search engineers, Glean achieved $100M ARR in three years and a $7.2B valuation (2025). It connects 100+ enterprise apps with real-time access controls, supports 15+ LLMs, and offers comprehensive APIs with 4-language SDKs. Trade-offs: enterprise-only sales (~$50/user/month, ~$60K minimum), no consumer messaging channels, and premium positioning over plug-and-play simplicity. Founded in 2019, headquartered in Palo Alto, CA, the platform has established itself as a reliable solution in the RAG space.
Overall Rating
96/100
Starting Price
$50/mo
About Vertex AI
Vertex AI is google's unified ml platform with gemini models and automl. Vertex AI is Google Cloud's comprehensive machine learning platform that unifies data engineering, data science, and ML engineering workflows. It offers state-of-the-art Gemini models with industry-leading context windows up to 2 million tokens, AutoML capabilities, and enterprise-grade infrastructure for building, deploying, and scaling AI applications. Founded in 2008, headquartered in Mountain View, CA, the platform has established itself as a reliable solution in the RAG space.
Overall Rating
88/100
Starting Price
Custom
Key Differences at a Glance
In terms of user ratings, Glean in overall satisfaction. From a cost perspective, Vertex AI offers more competitive entry pricing. The platforms also differ in their primary focus: Enterprise RAG versus AI Chatbot. These differences make each platform better suited for specific use cases and organizational requirements.
⚠️ What This Comparison Covers
We'll analyze features, pricing, performance benchmarks, security compliance, integration capabilities, and real-world use cases to help you determine which platform best fits your organization's needs. All data is independently verified from official documentation and third-party review platforms.
Detailed Feature Comparison
Glean
Vertex AI
CustomGPTRECOMMENDED
Data Ingestion & Knowledge Sources
100+ native connectors covering major enterprise categories
Cloud Storage: Google Drive, SharePoint, OneDrive, Dropbox, Box
Communication: Slack, Microsoft Teams, Gmail, Outlook, Zoom
Indexing API: 10 requests/second for bulk operations, ProcessAll limited to once per 3 hours
Pulls in both structured and unstructured data straight from Google Cloud Storage, handling files like PDF, HTML, and CSV (Vertex AI Search Overview).
Taps into Google’s own web-crawling muscle to fold relevant public website content into your index with minimal fuss (Towards AI Vertex AI Search).
Keeps everything current with continuous ingestion and auto-indexing, so your knowledge base never falls out of date.
Lets you ingest more than 1,400 file formats—PDF, DOCX, TXT, Markdown, HTML, and many more—via simple drag-and-drop or API.
Crawls entire sites through sitemaps and URLs, automatically indexing public help-desk articles, FAQs, and docs.
Turns multimedia into text on the fly: YouTube videos, podcasts, and other media are auto-transcribed with built-in OCR and speech-to-text.
View Transcription Guide
Connects to Google Drive, SharePoint, Notion, Confluence, HubSpot, and more through API connectors or Zapier.
See Zapier Connectors
Supports both manual uploads and auto-sync retraining, so your knowledge base always stays up to date.
L L M Model Options
Model Hub supports 15+ LLMs across multiple hosting providers
OpenAI: GPT-3.5, GPT-4
Azure OpenAI: GPT models
Google Vertex AI: Gemini 1.5 Pro
Amazon Bedrock: Claude 3 Sonnet
Per-step model selection: Different LLMs for each workflow step
Temperature controls: Factual, balanced, or creative output settings
Model tiers: Basic, Standard, Premium (premium consumes FlexCredits on Enterprise Flex)
Two access options: Glean Universal Key (managed) or Customer Key (BYOK)
Zero data retention: Customer data never used for model training
Automatic model updates: Deprecated models replaced with latest versions
Automatic routing: Optimizes using best-in-class models per query type
Connects to Google’s own generative models—PaLM 2, Gemini—and can call external LLMs via API if you prefer (Google Cloud Vertex AI Models).
Lets you pick models based on your balance of cost, speed, and quality.
Supports prompt-template tweaks so you can steer tone, format, and citation rules.
Taps into top models—OpenAI’s GPT-5.1 series, GPT-4 series, and even Anthropic’s Claude for enterprise needs (4.5 opus and sonnet, etc ).
Automatically balances cost and performance by picking the right model for each request.
Model Selection Details
Uses proprietary prompt engineering and retrieval tweaks to return high-quality, citation-backed answers.
Handles all model management behind the scenes—no extra API keys or fine-tuning steps for you.
Performance & Accuracy
74% human-agreement rate on AI Evaluator benchmarks
25% precision increases reported in customer case studies
20% response time decreases documented
141% ROI over 3 years (Forrester Total Economic Impact study)
$15.6M NPV for composite organizations
110 hours saved per employee annually
AI Evaluator metrics: Context relevance, recall, answer relevance, completeness, groundedness
Ships solid REST APIs and client libraries for weaving Vertex AI into web apps, mobile apps, or enterprise portals (Google Cloud Vertex AI API Docs).
Plays nicely with other Google Cloud staples—BigQuery, Dataflow, and more—and even supports low-code connectors via Logic Apps and PowerApps (Google Cloud Connectors).
Lets you deploy conversational agents wherever you need them, whether that’s a bespoke front-end or an embedded widget.
Embeds easily—a lightweight script or iframe drops the chat widget into any website or mobile app.
Offers ready-made hooks for Slack, Zendesk, Confluence, YouTube, Sharepoint, 100+ more.
Explore API Integrations
Connects with 5,000+ apps via Zapier and webhooks to automate your workflows.
Supports secure deployments with domain allowlisting and a ChatGPT Plugin for private use cases.
Hosted CustomGPT.ai offers hosted MCP Server with support for Claude Web, Claude Desktop, Cursor, ChatGPT, Windsurf, Trae, etc.
Read more here.
Embeddings control: Via Indexing API and custom datasources
Performance benchmarks: Strong (Forrester TEI, customer case studies)
Permissions & governance: Best-in-class (real-time enforcement, Active Data Governance)
Best for: Large enterprises requiring permissions-aware RAG with compliance needs
Not ideal for: SMBs with budget constraints, teams needing consumer messaging channels
Platform Type: TRUE ENTERPRISE RAG-AS-A-SERVICE PLATFORM - fully managed orchestration service for production-ready RAG implementations with developer-first APIs
Core Architecture: Vertex AI RAG Engine (GA 2024) streamlines complex process of retrieving relevant information and feeding it to LLMs, with managed infrastructure handling data retrieval and LLM integration
API-First Design: Comprehensive easy-to-use API enabling rapid prototyping with VPC-SC security controls and CMEK support (data residency and AXT not supported)
Managed Orchestration: Developers focus on building applications rather than managing infrastructure - handles complexities of vector search, chunking, embedding, and retrieval automatically
Customization Depth: Various parsing, chunking, annotation, embedding, vector storage options with open-source model integration for specialized domain requirements
Developer Experience: "Sweet spot" for developers using Vertex AI to implement RAG-based LLMs - balances ease of use of Vertex AI Search with power of custom RAG pipeline
Target Market: Enterprise developers already using GCP infrastructure wanting managed RAG without building from scratch, organizations needing PaLM 2/Gemini models with Google's search capabilities
RAG Technology Leadership: Hybrid search with advanced reranking, factual-consistency scoring, Google web-crawling infrastructure for public content ingestion, sub-millisecond responses globally
Deployment Flexibility: Public cloud, VPC, or on-premise deployments with multi-region scalability, seamless GCP integration (BigQuery, Dataflow, Cloud Functions), and unified billing
Enterprise Readiness: SOC 2/ISO/HIPAA/GDPR compliance, customer-managed encryption keys, Private Link, detailed audit logs, Google Cloud Operations Suite monitoring
Use Case Fit: Ideal for personalized investment advice and risk assessment, accelerated drug discovery and personalized treatment plans, enhanced due diligence and contract review, GCP-native organizations wanting unified AI infrastructure
Competitive Positioning: Positioned between no-code platforms (WonderChat, Chatbase) and custom implementations (LangChain) - offers managed RAG with enterprise-grade capabilities for GCP ecosystem
LIMITATION: GCP lock-in: Strongest value for GCP customers - less compelling for AWS/Azure-native organizations vs platform-agnostic alternatives like CustomGPT or Cohere
LIMITATION: Google models only: PaLM 2/Gemini family exclusively - no native support for Claude, GPT-4, or open-source models compared to multi-model platforms
Core Architecture: Serverless RAG infrastructure with automatic embedding generation, vector search optimization, and LLM orchestration fully managed behind API endpoints
API-First Design: Comprehensive REST API with well-documented endpoints for creating agents, managing projects, ingesting data (1,400+ formats), and querying chat
API Documentation
Developer Experience: Open-source Python SDK (customgpt-client), Postman collections, OpenAI API endpoint compatibility, and extensive cookbooks for rapid integration
No-Code Alternative: Wizard-style web dashboard enables non-developers to upload content, brand widgets, and deploy chatbots without touching code
Hybrid Target Market: Serves both developer teams wanting robust APIs AND business users seeking no-code RAG deployment - unique positioning vs pure API platforms (Cohere) or pure no-code tools (Jotform)
RAG Technology Leadership: Industry-leading answer accuracy (median 5/5 benchmarked), 1,400+ file format support with auto-transcription, proprietary anti-hallucination mechanisms, and citation-backed responses
Benchmark Details
Deployment Flexibility: Cloud-hosted SaaS with auto-scaling, API integrations, embedded chat widgets, ChatGPT Plugin support, and hosted MCP Server for Claude/Cursor/ChatGPT
Enterprise Readiness: SOC 2 Type II + GDPR compliance, full white-labeling, domain allowlisting, RBAC with 2FA/SSO, and flat-rate pricing without per-query charges
Use Case Fit: Ideal for organizations needing both rapid no-code deployment AND robust API capabilities, teams handling diverse content types (1,400+ formats, multimedia transcription), and businesses requiring production-ready RAG without building ML infrastructure from scratch
Competitive Positioning: Bridges the gap between developer-first platforms (Cohere, Deepset) requiring heavy coding and no-code chatbot builders (Jotform, Kommunicate) lacking API depth - offers best of both worlds
Competitive Positioning
vs CustomGPT: Enterprise-premium vs developer-friendly; permissions-aware AI vs flexible customization
vs Zendesk: Enterprise search + RAG vs customer service platform
Unique strength: Real-time permissions-aware AI across 100+ datasources (no competitor matches this)
Target audience: Large enterprises (1K-100K users) with complex permission hierarchies
Pricing barrier: ~$50/user/month with ~$60K minimum excludes SMBs
Enterprise focus: Security, governance, compliance over plug-and-play simplicity
Market position: Enterprise-grade Google Cloud AI platform combining Vertex AI Search with Conversation for production-ready RAG, deeply integrated with GCP ecosystem
Target customers: Organizations already invested in Google Cloud infrastructure, enterprises requiring PaLM 2/Gemini models with Google's search capabilities, and companies needing global scalability with multi-region deployment and GCP service integration
Key competitors: Azure AI Search, AWS Bedrock, OpenAI Enterprise, Coveo, and custom RAG implementations
Competitive advantages: Native Google PaLM 2/Gemini models with external LLM support, Google's web-crawling infrastructure for public content ingestion, seamless GCP integration (BigQuery, Dataflow, Cloud Functions), hybrid search with advanced reranking, SOC/ISO/HIPAA/GDPR compliance with customer-managed keys, global infrastructure for millisecond responses worldwide, and Google Cloud Operations Suite for comprehensive monitoring
Pricing advantage: Pay-as-you-go with free tier for development; competitive for GCP customers leveraging existing enterprise agreements and volume discounts; autoscaling prevents overprovisioning; best value for organizations with GCP infrastructure wanting unified billing and managed services
Use case fit: Best for organizations already using GCP infrastructure (BigQuery, Cloud Functions), enterprises needing Google's proprietary models (PaLM 2, Gemini) with web-crawling capabilities, and companies requiring global scalability with multi-region deployment and tight integration with GCP analytics and data pipelines
Market position: Leading all-in-one RAG platform balancing enterprise-grade accuracy with developer-friendly APIs and no-code usability for rapid deployment
Target customers: Mid-market to enterprise organizations needing production-ready AI assistants, development teams wanting robust APIs without building RAG infrastructure, and businesses requiring 1,400+ file format support with auto-transcription (YouTube, podcasts)
Key competitors: OpenAI Assistants API, Botsonic, Chatbase.co, Azure AI, and custom RAG implementations using LangChain
Competitive advantages: Industry-leading answer accuracy (median 5/5 benchmarked), 1,400+ file format support with auto-transcription, SOC 2 Type II + GDPR compliance, full white-labeling included, OpenAI API endpoint compatibility, hosted MCP Server support (Claude, Cursor, ChatGPT), generous data limits (60M words Standard, 300M Premium), and flat monthly pricing without per-query charges
Pricing advantage: Transparent flat-rate pricing at $99/month (Standard) and $449/month (Premium) with generous included limits; no hidden costs for API access, branding removal, or basic features; best value for teams needing both no-code dashboard and developer APIs in one platform
Use case fit: Ideal for businesses needing both rapid no-code deployment and robust API capabilities, organizations handling diverse content types (1,400+ formats, multimedia transcription), teams requiring white-label chatbots with source citations for customer-facing or internal knowledge projects, and companies wanting all-in-one RAG without managing ML infrastructure
A I Models
Model Hub supports 15+ LLMs across multiple hosting providers with per-step model selection
OpenAI: GPT-3.5, GPT-4 via OpenAI or Azure OpenAI endpoints
Google Vertex AI: Gemini 1.5 Pro with multimodal capabilities
Amazon Bedrock: Claude 3 Sonnet for high-accuracy enterprise use cases
Temperature controls: Factual, balanced, or creative output settings per workflow
Model tiers: Basic, Standard, Premium (premium consumes FlexCredits on Enterprise Flex plan)
Two access options: Glean Universal Key (managed) or Customer Key (BYOK) for data sovereignty
Zero data retention: Customer data never used for model training with automatic model updates
Automatic routing: Optimizes using best-in-class models per query type for accuracy and cost
Google proprietary models: PaLM 2 (Pathways Language Model) and Gemini 2.0/2.5 family (Pro, Flash variants) optimized for enterprise workloads
Gemini 2.5 Pro: $1.25-$2.50 per million input tokens, $10-$15 per million output tokens for advanced reasoning and multimodal understanding
Gemini 2.5 Flash: $0.30 per million input tokens, $2.50 per million output tokens for cost-effective high-speed inference
Gemini 2.0 Flash: $0.15 per million input tokens, $0.60 per million output tokens for ultra-low-cost deployment
External LLM support: Can call external LLMs via API if preferring non-Google models for specific use cases
Model selection flexibility: Choose models based on balance of cost, speed, and quality requirements per use case
Prompt template customization: Configure tone, format, and citation rules through prompt engineering
Temperature and token controls: Adjust generation parameters (temperature, max tokens) for domain-specific response characteristics
Primary models: GPT-5.1 and 4 series from OpenAI, and Anthropic's Claude 4.5 (opus and sonnet) for enterprise needs
Automatic model selection: Balances cost and performance by automatically selecting the appropriate model for each request
Model Selection Details
Proprietary optimizations: Custom prompt engineering and retrieval enhancements for high-quality, citation-backed answers
Managed infrastructure: All model management handled behind the scenes - no API keys or fine-tuning required from users
Anti-hallucination technology: Advanced mechanisms ensure chatbot only answers based on provided content, improving trust and factual accuracy
R A G Capabilities
Hybrid search: Combines semantic (vector-based) and lexical (keyword) approaches for maximum accuracy
Knowledge Graph Framework: Proprietary anchors and signals across enterprise data with rich, scalable crawler
LLM Control Layer: Optimizes and controls LLM outputs with permission-safe document retrieval and ranking
Real-time permissions enforcement: Users only see authorized content with identity crawling and connector-level permission mirroring
Context-aware query rewriting: LLM determines optimal query set with enterprise-specific rewrites
Hallucination prevention: RAG grounding, permission-aware retrieval, citation/source attribution for every answer
74% human-agreement rate on AI Evaluator benchmarks with 25% precision increases in customer case studies
141% ROI over 3 years: $15.6M NPV for composite organizations, 110 hours saved per employee annually (Forrester)
Permissions-aware AI (unique): Real-time access control enforcement across all 100+ datasources - no competitor matches this capability
Hybrid search: Combines semantic vector search with keyword (BM25) matching for strong retrieval accuracy across query types
Advanced reranking: Multi-stage reranking pipeline cuts hallucinations and ensures factual consistency in generated responses
Google web-crawling: Taps into Google's web-crawling infrastructure to ingest relevant public website content into indexes automatically
Continuous ingestion: Keeps knowledge base current with automatic indexing and auto-refresh preventing stale data
Fine-grained indexing control: Set chunk sizes, metadata tags, and retrieval parameters to shape semantic search behavior
Semantic/lexical weighting: Adjust balance between semantic and keyword search per query type for optimal retrieval
Structured/unstructured data: Handles both structured data (BigQuery, Cloud SQL) and unstructured documents (PDF, HTML, CSV) from Google Cloud Storage
Factual consistency scoring: Hybrid search + reranking returns factual-consistency score with every answer for reliability assessment
Custom cognitive skills: Slot in custom processing or open-source models for specialized domain requirements
Core architecture: GPT-4 combined with Retrieval-Augmented Generation (RAG) technology, outperforming OpenAI in RAG benchmarks
RAG Performance
Anti-hallucination technology: Advanced mechanisms reduce hallucinations and ensure responses are grounded in provided content
Benchmark Details
Automatic citations: Each response includes clickable citations pointing to original source documents for transparency and verification
Optimized pipeline: Efficient vector search, smart chunking, and caching for sub-second reply times
Scalability: Maintains speed and accuracy for massive knowledge bases with tens of millions of words
Context-aware conversations: Multi-turn conversations with persistent history and comprehensive conversation management
Source verification: Always cites sources so users can verify facts on the spot
Use Cases
Enterprise knowledge retrieval: Unified search across 100+ datasources (Google Drive, SharePoint, Confluence, Salesforce, Zendesk, GitHub, Slack) for 10K-100K user organizations
Permissions-aware search: Complex permission hierarchies requiring real-time enforcement - healthcare, finance, legal industries with sensitive data access controls
AI agents and automation: 30+ prebuilt agents for sales, engineering, IT, HR use cases with workflow automation capabilities
Developer-friendly RAG: Official SDKs (Python, Java, Go, TypeScript), LangChain integration, MCP Server for Claude Desktop/Cursor/VS Code
Active Data Governance: Continuous scanning with 100+ predefined infotypes (PII, PCI, M&A) and customizable policies with auto-hide
Cloud-Prem deployment: Customer-hosted in AWS or GCP for regulated industries requiring full data residency control
NOT suitable for: SMBs with <100 users or <$60K budgets, simple document Q&A without permission requirements, consumer messaging channels (WhatsApp, Telegram)
GCP-native organizations: Perfect for companies already using BigQuery, Cloud Functions, Dataflow wanting unified AI infrastructure
Global enterprise deployments: Multi-region deployment with Google's global infrastructure for millisecond responses worldwide
Public content ingestion: Leverage Google's web-crawling muscle to automatically fold relevant public web content into knowledge bases
Multimodal understanding: Gemini models process and reason over text, images, videos, and code for rich content analysis
Google Workspace integration: Seamless integration with Gmail, Docs, Sheets for content-heavy workflows within Workspace ecosystem
BigQuery analytics integration: Tight coupling with BigQuery for analytics on conversation data, user behavior, and system performance
Enterprise conversational AI: Build customer service bots, internal knowledge assistants, and autonomous agents grounded in company data
Regulated industries: Healthcare, finance, government with SOC/ISO/HIPAA/GDPR compliance and customer-managed encryption keys
Customer support automation: AI assistants handling common queries, reducing support ticket volume, providing 24/7 instant responses with source citations
Internal knowledge management: Employee self-service for HR policies, technical documentation, onboarding materials, company procedures across 1,400+ file formats
Sales enablement: Product information chatbots, lead qualification, customer education with white-labeled widgets on websites and apps
Documentation assistance: Technical docs, help centers, FAQs with automatic website crawling and sitemap indexing
Educational platforms: Course materials, research assistance, student support with multimedia content (YouTube transcriptions, podcasts)
Healthcare information: Patient education, medical knowledge bases (SOC 2 Type II compliant for sensitive data)
Gemini 2.0 Flash: $0.15/M input tokens, $0.60/M output tokens for ultra-low-cost deployment at scale
Imagen pricing: $0.0001 per image for specific endpoints enabling visual content generation
Autoscaling: Scales effortlessly on Google's global backbone with automatic resource adjustment preventing overprovisioning
Enterprise agreements: Volume discounts and committed use discounts for GCP customers with existing enterprise agreements
Unified billing: Single GCP bill for Vertex AI, BigQuery, Cloud Functions, and all Google Cloud services
Standard Plan: $99/month or $89/month annual - 10 custom chatbots, 5,000 items per chatbot, 60 million words per bot, basic helpdesk support, standard security
View Pricing
Premium Plan: $499/month or $449/month annual - 100 custom chatbots, 20,000 items per chatbot, 300 million words per bot, advanced support, enhanced security, additional customization
Enterprise Plan: Custom pricing - Comprehensive AI solutions, highest security and compliance, dedicated account managers, custom SSO, token authentication, priority support with faster SLAs
Enterprise Solutions
7-Day Free Trial: Full access to Standard features without charges - available to all users
Annual billing discount: Save 10% by paying upfront annually ($89/mo Standard, $449/mo Premium)
Flat monthly rates: No per-query charges, no hidden costs for API access or white-labeling (included in all plans)
Managed infrastructure: Auto-scaling cloud infrastructure included - no additional hosting or scaling fees
Support & Documentation
Standard support: 24x5 (Mon-Fri) via portal, email, Slack Connect channels
Premium support: 24x7 for critical issues with additional fee
Dedicated CSMs: Enterprise accounts with hands-on onboarding and regular business reviews
Excellent documentation: developers.glean.com with OpenAPI specs, CodeSandbox demos, comprehensive API references
Official SDKs: Python (pip install glean), Java (Maven), Go, TypeScript with async support and framework integrations
Web SDK: @gleanwork/web-sdk for embeddable components (chat, search, autocomplete, recommendations)
GitHub repositories: github.com/gleanwork with SDK repositories and sample projects
NO FedRAMP certification: Not suitable for US federal government deployments
Limited consumer channels: No native WhatsApp, Telegram integrations - designed for internal enterprise use only
Complex implementation: Initial indexing takes "few days" depending on data volume, requires enterprise IT coordination
Cross-language queries in early access: English query finding Spanish documents still in testing phase
Best for: Large enterprises (1K-100K users) with complex permission hierarchies, $60K+ budgets, and need for permissions-aware AI across 100+ datasources
NOT suitable for: SMBs, startups, simple document Q&A without permission requirements, organizations prioritizing transparent pricing
GCP ecosystem dependency: Strongest value for organizations already using Google Cloud - less compelling for AWS/Azure-native companies
No full drag-and-drop chatbot builder: Cloud console manages indexes and search settings, but not a complete no-code GUI like Tidio or WonderChat
Learning curve for non-GCP users: Teams unfamiliar with Google Cloud face steeper learning curve vs platform-agnostic alternatives
Model selection limited to Google: PaLM 2 and Gemini family only - no native Claude, GPT-4, or Llama support compared to multi-model platforms
Requires technical expertise: Deeper customization calls for developer skills - not suitable for non-technical teams without GCP experience
Pricing complexity: Pay-as-you-go model requires careful monitoring to prevent unexpected costs at scale
Overkill for simple use cases: Enterprise RAG capabilities and GCP integration unnecessary for basic FAQ bots or simple customer service
Vendor lock-in considerations: Deep GCP integration creates switching costs if migrating to alternative cloud providers in future
Managed service approach: Less control over underlying RAG pipeline configuration compared to build-your-own solutions like LangChain
Vendor lock-in: Proprietary platform - migration to alternative RAG solutions requires rebuilding knowledge bases
Model selection: Limited to OpenAI (GPT-5.1 and 4 series) and Anthropic (Claude, opus and sonnet 4.5) - no support for other LLM providers (Cohere, AI21, open-source models)
Pricing at scale: Flat-rate pricing may become expensive for very high-volume use cases (millions of queries/month) compared to pay-per-use models
Customization limits: While highly configurable, some advanced RAG techniques (custom reranking, hybrid search strategies) may not be exposed
Language support: Supports 90+ languages but performance may vary for less common languages or specialized domains
Real-time data: Knowledge bases require re-indexing for updates - not ideal for real-time data requirements (stock prices, live inventory)
Enterprise features: Some advanced features (custom SSO, token authentication) only available on Enterprise plan with custom pricing
Core Agent Features
Autonomous AI agents: Agents use AI to understand tasks and take action on behalf of users from answering questions and retrieving information to executing work autonomously
Natural language agent builder: Build agents by describing desired output in simple natural language - Glean understands goal and designs complex multi-step workflows
Agentic reasoning engine: LLM-agnostic engine enables agents to go beyond retrieval and generation - powers sophisticated automation and decision-making by understanding outcomes, building multi-step plans, and using action library
100+ native actions: Supports 100+ new native actions across Slack, Microsoft Teams, Salesforce, Jira, GitHub, Google Workspace and other applications
MCP host support: Gives agents dramatically larger surface area to operate across enterprise applications
Human-in-the-loop design: Agents can autonomously do work end-to-end with human review checkpoints - process customer support tickets, conduct research, prepare responses for employee review before execution
Vibe coding: Upgraded builder makes agent creation as simple as chatting - anyone (not just developers) can create and refine agents without understanding or interacting with code
Grounded in enterprise data: Autonomous agents grounded in most relevant authoritative information for confident work automation
Automatic agent triggering: Orchestrates agents automatically based on schedules or events and surfaces agent recommendations across enterprise
Visual and conversational workflow design: Turn ideas into structured workflows using simple natural language prompts or visual builder
Vertex AI Agent Engine: Build autonomous agents with short-term and long-term memory for managing sessions and recalling past conversations and preferences
Agent Builder (April 2024): Visual drag-and-drop interface to create AI agents without code, with advanced integrations to LlamaIndex, LangChain, and RAG capabilities combining LLM-generated responses with real-time data retrieval
Multi-turn conversation context: Agent Engine Sessions store individual user-agent interactions as definitive sources for conversation context, enabling coherent multi-turn interactions
Memory Bank: Stores and retrieves information from sessions to personalize agent interactions and maintain context across conversations
Agent orchestration: Agents can maintain context across systems, discover each other's capabilities dynamically, and negotiate interaction formats
Human handoff capabilities: Generate interaction summaries, citations, and other data to facilitate handoffs between AI apps and human agents with full conversation history
Observability tools: Google Cloud Trace, Cloud Monitoring, and Cloud Logging provide comprehensive understanding of agent behavior and performance
Action-based agents: Take actions based on conversations and interact with back-end transactional systems in an automated manner
Data source tuning: Tune chats with various data sources including conversation histories to enable smooth transitions and continuous improvement
LIMITATION: Technical expertise required: Agent Builder introduced visual interface in 2024, but deeper customization and orchestration still require GCP/developer skills
LIMITATION: No native lead capture: Unlike specialized chatbot platforms, Vertex AI focuses on enterprise conversational AI rather than marketing automation features
Custom AI Agents: Build autonomous agents powered by GPT-4 and Claude that can perform tasks independently and make real-time decisions based on business knowledge
Decision-Support Capabilities: AI agents analyze proprietary data to provide insights, recommendations, and actionable responses specific to your business domain
Multi-Agent Systems: Deploy multiple specialized AI agents that can collaborate and optimize workflows in areas like customer support, sales, and internal knowledge management
Memory & Context Management: Agents maintain conversation history and persistent context for coherent multi-turn interactions
View Agent Documentation
Tool Integration: Agents can trigger actions, integrate with external APIs via webhooks, and connect to 5,000+ apps through Zapier for automated workflows
Hyper-Accurate Responses: Leverages advanced RAG technology and retrieval mechanisms to deliver context-aware, citation-backed responses grounded in your knowledge base
Continuous Learning: Agents improve over time through automatic re-indexing of knowledge sources and integration of new data without manual retraining
Additional Considerations
Cannot create content directly: Glean focuses purely on search and retrieval - not suitable for organizations needing content creation within platform
Platform designed for large organizations: Feature set and pricing optimized for large enterprises - smaller teams may find it overkill and less cost-effective
AI production challenges: 68% of organizations report moving only 30% or fewer AI experiments into full production highlighting persistent scaling difficulties beyond proof-of-concept
Integration complexity: Requires strategic overhaul of processes to ensure seamless technology incorporation into existing workflows
Change management: Overcoming resistance to change demands strong leadership and commitment to fostering innovation and adaptability environment
Data reliability monitoring: Potential for inaccuracies in AI outputs necessitates rigorous monitoring frameworks to ensure data reliability and trustworthiness
Cybersecurity concerns: As AI deployment expands, cybersecurity threats become more pronounced requiring enhanced protective measures for sensitive information
Bias in AI models: Models can inadvertently learn and replicate biases in training data leading to unfair or discriminatory outcomes particularly in hiring, customer service, legal decisions
Training investment required: Enterprises must invest in training workforce to effectively use AI tools - upskilling employees, hiring AI talent, or partnering with consultants
Security risks and shadow IT: Many organizations hesitate due to uncertainties from security risks and shadow IT - ad hoc generative AI adoption comes with heavy risks and costs
Packs hybrid search and reranking that return a factual-consistency score with every answer.
Supports public cloud, VPC, or on-prem deployments if you have strict data-residency rules.
Gets regular updates as Google pours R&D into RAG and generative AI capabilities.
Slashes engineering overhead with an all-in-one RAG platform—no in-house ML team required.
Gets you to value quickly: launch a functional AI assistant in minutes.
Stays current with ongoing GPT and retrieval improvements, so you’re always on the latest tech.
Balances top-tier accuracy with ease of use, perfect for customer-facing or internal knowledge projects.
Core Chatbot Features
Glean Chat interface: Primary interface for interacting with Glean Assistant offering familiar chat-like experience enabling natural conversations with company knowledge base
Multi-turn conversations: Supports conversational AI with natural language and context awareness maintaining context across conversation turns
Streaming responses: Real-time response streaming for better user experience with automatic source citations for transparency
Chatbot context understanding: Understands thread and sequence of conversations tracking references like "their" and "they" across multiple exchanges
Enterprise knowledge integration: Works across all company apps and knowledge sources including Microsoft 365, Google Workspace, Salesforce, Jira, GitHub and nearly 100 more applications
Personalization and security: Delivers answers highly customized to each user based on deep understanding of company content, employees, and activity while adhering to real-time enterprise data permissions and governance rules
Citation and transparency: Provides full linking to source information across documents, conversations and applications for transparency and trust
Simple chatbot API: Powerful tool for integrating conversational AI into products creating custom conversational interfaces leveraging Glean's AI capabilities
Use case flexibility: Build chatbots answering customer questions using help documentation, FAQs, knowledge bases or create internal tools helping employees find company policies, procedures, documentation
After analyzing features, pricing, performance, and user feedback, both Glean and Vertex AI are capable platforms that serve different market segments and use cases effectively.
When to Choose Glean
You value permissions-aware ai is genuinely differentiated - real-time enforcement across 100+ datasources addresses critical enterprise concern
Model flexibility without vendor lock-in - 15+ LLMs with per-step selection and bring-your-own-key option
Best For: Permissions-aware AI is genuinely differentiated - real-time enforcement across 100+ datasources addresses critical enterprise concern
When to Choose Vertex AI
You value industry-leading 2m token context window with gemini models
Comprehensive ML platform covering entire AI lifecycle
Deep integration with Google Cloud ecosystem
Best For: Industry-leading 2M token context window with Gemini models
Migration & Switching Considerations
Switching between Glean and Vertex AI requires careful planning. Consider data export capabilities, API compatibility, and integration complexity. Both platforms offer migration support, but expect 2-4 weeks for complete transition including testing and team training.
Pricing Comparison Summary
Glean starts at $50/month, while Vertex AI begins at custom pricing. Total cost of ownership should factor in implementation time, training requirements, API usage fees, and ongoing support. Enterprise deployments typically see annual costs ranging from $10,000 to $500,000+ depending on scale and requirements.
Our Recommendation Process
Start with a free trial - Both platforms offer trial periods to test with your actual data
Define success metrics - Response accuracy, latency, user satisfaction, cost per query
Test with real use cases - Don't rely on generic demos; use your production data
Evaluate total cost - Factor in implementation time, training, and ongoing maintenance
Check vendor stability - Review roadmap transparency, update frequency, and support quality
For most organizations, the decision between Glean and Vertex AI comes down to specific requirements rather than overall superiority. Evaluate both platforms with your actual data during trial periods, focusing on accuracy, latency, ease of integration, and total cost of ownership.
📚 Next Steps
Ready to make your decision? We recommend starting with a hands-on evaluation of both platforms using your specific use case and data.
• Review: Check the detailed feature comparison table above
• Test: Sign up for free trials and test with real queries
• Calculate: Estimate your monthly costs based on expected usage
• Decide: Choose the platform that best aligns with your requirements
Last updated: December 15, 2025 | This comparison is regularly reviewed and updated to reflect the latest platform capabilities, pricing, and user feedback.
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DevRel at CustomGPT.ai. Passionate about AI and its applications. Here to help you navigate the world of AI tools and make informed decisions for your business.
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