AI Training Data Services

The human experts your AI models need to get smarter

We provide certified annotation, expert feedback, and model evaluation from a vetted network of senior professionals—with a benchmark-measured quality scorecard on every batch.

We’ll explore your technology goals and challenges
You’ll get expert insights on the best path forward
We’ll outline next steps to bring your solution to life
PROMISED EXPERTISE

Certified experts and a quality score on every batch

Certified expert network

Every expert is certified in their domain before they touch your data, giving teams AI data services and AI services for expert-led annotation and evaluation. This model combines measurable quality with flexible training capabilities, backed by deep domain knowledge and a network equipped to support domain-specific annotation needs. Expert-led annotation and evaluation also strengthen fine-tuning for specialist or enterprise models.

Benchmark-measured data quality

Every batch of annotated data ships with inter-annotator agreement rates, gold-set accuracy, error analysis, and expert credentials per task. Our expert network brings deep domain knowledge to specialist annotation work, essential for supervised machine learning models. We build model and dataset benchmarks as a product, which is why our quality claims arrive pre-measured. That same expert network is part of our training capabilities.

Structurally neutral

No lab owns a stake in FullStack, no lab has invested in us, and we don't compete with your model. Your roadmap stays confidential by construction rather than by promise.

Synthetic data, expert-verified

We generate synthetic training data where it's efficient and apply expert verification where accuracy matters. For certain tasks, well-designed synthetic data can match or exceed the performance of real data when specialists validate it.

We'll scope a real batch of your actual work, not a sample task.
When possible, we’ll compare our results head-to-head with your incumbent vendor.
You'll get it back with a full quality scorecard attached.
Case Studies

Our client impact in action

The quality scorecard, published

The scorecard format is the proof: inter-annotator agreement, gold-set accuracy, error analysis, expert credentials per task, and throughput—the same document on every batch. Most vendors describe their quality process. We publish the artifact, because building the measurement is one of the things we sell.

Our own annotation pipeline

FullStack is building its expert network and platform to produce the training data and benchmarks for its own specialized models engagements, with AI evaluation scorecards for each batch, then publishing the pipeline metrics: quality scores, throughput, and expert certification stats.

That gives teams clearer proof on annotated outputs, labeled data, and what the scorecard confirms. Labels are crucial for making data teachable. This supports responsible AI data workflows for artificial intelligence programs and AI training data management, including high-quality labeled data for compliant model development.

How we route our own AI stack

FullStack is building and running its own gateway across internal AI usage on Connect and Labs tooling to produce AI training data for specialized models engagements, along with benchmarks that support artificial intelligence model development with high-quality labeled data and plans to publish the resulting metrics.

AI training data teaches models patterns from examples. Manual annotation is slow and error-prone, and labeling is often the most expensive part of data preparation.

testimonials

What our clients are saying

FullStack’s deep understanding of BenjaminWest’s needs, coupled with consistent updates, made the collaboration seamless and the outcome outstanding.
Joe Eikelberner, COO
BenjaminWest
FullStack acted as true partners and advisors. The expertise around AI and the level of developers, engineers—whatever role it was that came to the table—was just phenomenal.
Marisa Kopec, CEO
Lux Research
Speed is only the byproduct; the real value is better software and better use of our people.
Raj Tatta, VP of Engineering
Paciolan
FullStack turned our vision for The Launchpad into reality. Their intuitive design approach delivered an app that provides IT buyers a seamless and hassle-free experience, effortlessly connecting them with the ideal tech vendors.
Tonya Turrell, Founder & CEO
Technology Match
FullStack completely transformed our company's app, breathing new life into how we service our customer base. Their innovative and collaborative team delivered an application experience that we're proud to have in the market!
Jay Williams, Software Manager
Green Mountain Power
FullStack’s deep understanding of BenjaminWest’s needs, coupled with consistent updates, made the collaboration seamless and the outcome outstanding.
Joe Eikelberner, COO
BenjaminWest
FullStack acted as true partners and advisors. The expertise around AI and the level of developers, engineers—whatever role it was that came to the table—was just phenomenal.
Marisa Kopec, CEO
Lux Research
Speed is only the byproduct; the real value is better software and better use of our people.
Raj Tatta, VP of Engineering
Paciolan
FullStack turned our vision for The Launchpad into reality. Their intuitive design approach delivered an app that provides IT buyers a seamless and hassle-free experience, effortlessly connecting them with the ideal tech vendors.
Tonya Turrell, Founder & CEO
Technology Match
FullStack completely transformed our company's app, breathing new life into how we service our customer base. Their innovative and collaborative team delivered an application experience that we're proud to have in the market!
Jay Williams, Software Manager
Green Mountain Power
MOVING SAFELY

Run the pilot. Read the scorecard.

Every engagement opens with a paid pilot: a fixed-scope batch of your real workload, delivered through the platform by certified experts, returned with a full quality scorecard. Measurement is part of what it takes to operationalize AI inside the business. We also help enterprises address head-on the issues that erode outcomes over time, since inaccessible data, poor quality inputs, and data debt can undermine quality retention and cost control if not addressed.

First batch in 2–4 weeks*

You get agreement rates, error analysis, expert credentials per task, and throughput before committing to volume.

Judge us against your incumbent

Where the same tasks can be run twice, we'll show you the head-to-head—the fair way for a lab qualifying a new specialist data annotation supplier to compare us against what it already has. Buyers in this market have been promised experts and delivered crowds, so measured quality on your own tasks is the only fair test.

We focus on expert-led data work

Routine, high-volume pre-labeling is being automated away by foundation models. If that's what you need, a BPO annotation vendor will serve you better and cheaper. We work at the expert layer.

The platform is in development

Our expert-network platform is being built now, seeded by Connect's existing vetted-professional network. Delivery today runs as managed pods on that foundation—worth knowing whether you're an enterprise training your first specialist model or a lab qualifying a new supplier.

*These are typical time estimates and actual times may differ based on project complexity and scope.
COMPREHENSIVE SOLUTIONS

Explore FullStack's expert data services

As high-quality public web data becomes more constrained, frontier labs increasingly rely on specialist post-training data. FullStack supports the full spectrum of specialist data work, from expert sourcing to measured delivery. Our AI training data services connect business goals with technical execution across the delivery stack. The gains now come from post-training—RLHF, expert preference data, RL environments, rubrics, and verification—much of which cannot be sourced from public corpora. It must be created and evaluated by domain experts.
  • Domain-credentialed pools: code, healthcare, legal, finance
  • Expert annotation across multiple modalities for AI training and large language models
  • RLHF and expert preference data for reinforcement learning
  • Model and dataset evaluation for effective AI models
  • Benchmark design and development
  • Rubric co-design and quality calibration for sentiment analysis
  • RL environment and verifier construction
  • Synthetic data generation with expert verification
  • Flexible data collection tailored to different validation and modeling needs
  • Locale-specific data in 400+ language variants, including native Spanish and Portuguese language data

Partner with FullStack and judge us on the data

Frontier and Near-Frontier Labs

Neutral by construction, at a bench nobody else has tapped

For labs buying post-training data at scale, we offer structural neutrality, a security and confidentiality posture built as a first-order deliverable, and senior bilingual experts from a region we've spent years recruiting in.
Enterprises Training Their Own Models

An annotation partner with AI model-development expertise

For first-time annotation buyers, we label your proprietary data, verify synthetic data where it's efficient, and hand you benchmark-grade quality measurement, from the team that also handles AI model creation, including support for regulated industries working with proprietary or sensitive content. We can apply entity recognition to unstructured data before annotation or model work when sensitive details need to be handled appropriately.
A tailored industry solution can also bring together advanced data engineering, custom software development, and ecosystem partnerships around the model-building work.
Our blog

Featured articles

What DeepSeek’s DSpark means for LLM performance in production

DeepSeek’s DSpark speculative decoding makes V4 models up to 85% faster per user. Learn what that means for your LLM stack in production.
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OpenAI's Terra, Luna, and Sol vs. Anthropic: Which wins what?

We benchmarked OpenAI and Anthropic on real engineering tasks. See how they compare on reliability, cost, and speed.
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Sonnet 5 is here: Which jobs it wins—and where Opus still leads

FullStack ran Sonnet 5 and two Opus builds through real enterprise tasks. There was no single winner—but a clear routing strategy that cuts costs without sacrificing results.
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Gate Fatigue: When Human Approval Stops Meaning Anything

Gate fatigue can weaken human oversight in AI workflows. Learn how to design approval gates that hold up as agent activity scales.
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How AI Agent Governance Is Moving Into Practice

AI governance is changing fast. Learn how businesses can manage AI agents, access controls, monitoring, and incident response.
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AI Adoption Is Now an Everyone Problem: What Walmart, The New York Times, and Honeywell’s Filings Reveal

AI adoption is reshaping retail and manufacturing. See what Walmart, The New York Times, and Honeywell filings reveal.
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Frequently Asked Questions

What do FullStack's AI training data services include?
We provide certified data annotation, expert feedback, and model evaluation from a vetted network of senior professionals. That covers post-training work such as RLHF and expert preference data, benchmark design, RL environments and verifiers, and locale-specific data in 400+ language variants. If you only need routine, high-volume pre-labeling, a BPO annotation vendor will serve you better and cheaper. FullStack works at the expert layer.
How does FullStack measure the quality of annotated data?
Every batch ships with a quality scorecard: inter-annotator agreement rates, gold-set accuracy, error analysis, expert credentials per task, and throughput. It is the same document on every batch, so you can check quality against your own tasks instead of relying on a description of our process.
What does the paid pilot involve, and how soon do we get results?
The pilot is a fixed-scope batch of your real workload, annotated by certified experts and returned with the full scorecard attached. The first batch typically arrives in 2-4 weeks, depending on project complexity and scope. Where the same tasks can be run twice, we also show a head-to-head against your incumbent data-annotation vendor.
Is FullStack independent from AI labs?
Yes. No lab owns a piece of FullStack, no lab has invested in us, and we don't compete with your model. Your roadmap stays confidential by construction rather than by promise, which matters for labs buying post-training data at scale.
Does FullStack use synthetic data, and how is it verified?
We generate synthetic training data where it's efficient and apply expert verification where accuracy matters. When specialists validate it, well-designed synthetic data can match or even exceed real data performance for a specific task. The aim is the best balance of cost and quality, not a fixed position on synthetic versus real data.