From REST to Reasoning Agents: Designing APIs for the AI Era
APIs have powered modern applications for decades, but AI agents and LLMs are rewriting the rules. Traditional RESTful patterns aren’t enough when your consumers are autonomous systems that demand machine-readable contracts, contextual hints, and self-discovery. This talk explores how to design APIs that work seamlessly for humans and reasoning agents alike. You’ll learn practical techniques for contract-first design, metadata enrichment, hypermedia navigation, and avoiding pitfalls like “agent drift.” Future-ready APIs start here.
APIs are no longer just for apps and developers—they’re now serving reasoning agents, LLMs, and automation platforms. To prepare for this shift, API design must evolve. In this session, we’ll explore:
- Why REST needs an upgrade → traditional design patterns weren’t built for autonomous consumers.
- Contract-first design → how OpenAPI/Swagger extensions make APIs machine-readable and agent-friendly.
- Function-calling formats → structuring endpoints so LLMs can parse, chain, and execute them reliably.
- Metadata enrichment → annotating APIs with contextual hints to improve interpretability for agents.
- Hypermedia navigation → when patterns like HAL and HATEOAS help AI agents self-discover functionality.
- Agent drift pitfalls → why autonomous consumers misinterpret APIs and how to mitigate it.
- Practical patterns for tomorrow’s APIs → real-world strategies to serve both human developers and reasoning agents.
Audience: Backend developers, API designers, architects
Takeaways:
- Design APIs that are both human- and machine-friendly
- Apply contract-first principles for LLM discoverability
- Avoid common pitfalls like agent drift and misinterpretation
About Rohit Bhardwaj
Rohit Bhardwaj is a Director of Architecture working at Salesforce. Rohit has extensive experience architecting multi-tenant cloud-native solutions in Resilient Microservices Service-Oriented architectures using AWS Stack. In addition, Rohit has a proven ability in designing solutions and executing and delivering transformational programs that reduce costs and increase efficiencies.
As a trusted advisor, leader, and collaborator, Rohit applies problem resolution, analytical, and operational skills to all initiatives and develops strategic requirements and solution analysis through all stages of the project life cycle and product readiness to execution.
Rohit excels in designing scalable cloud microservice architectures using Spring Boot and Netflix OSS technologies using AWS and Google clouds. As a Security Ninja, Rohit looks for ways to resolve application security vulnerabilities using ethical hacking and threat modeling. Rohit is excited about architecting cloud technologies using Dockers, REDIS, NGINX, RightScale, RabbitMQ, Apigee, Azul Zing, Actuate BIRT reporting, Chef, Splunk, Rest-Assured, SoapUI, Dynatrace, and EnterpriseDB. In addition, Rohit has developed lambda architecture solutions using Apache Spark, Cassandra, and Camel for real-time analytics and integration projects.
Rohit has done MBA from Babson College in Corporate Entrepreneurship, Masters in Computer Science from Boston University and Harvard University. Rohit is a regular speaker at No Fluff Just Stuff, UberConf, RichWeb, GIDS, and other international conferences.
Rohit loves to connect on http://www.productivecloudinnovation.com.
http://linkedin.com/in/rohit-bhardwaj-cloud or using Twitter at rbhardwaj1.