# ReasonBlocks

**Canonical:** https://apis.io/providers/reasonblocks/  
**Website:** https://reasonblocks.com  
**APIs profiled:** 9

ReasonBlocks is a Y Combinator (Spring 2026) startup building a drop-in runtime layer that makes production AI agents observable, self-correcting, and cheaper to run. The platform detects failing agent trajectories (loops and redundant work), compresses stale tool outputs and message histories to cut token spend, and builds a private learning library of reasoning patterns (E-traces) that steer future runs. It ships as a Python SDK with first-party integrations for LangChain, LangGraph, the OpenAI Agents SDK, and the Anthropic Claude / Claude Agent SDK, plus a language-agnostic REST API (rb-api) so any custom agent harness can wire in over three HTTP calls. Reported results include a 42% accuracy gain and ~52% token reduction on SWE-bench Pro.

## Kin Score — 37.2 / 100 (thin)

Scored 2026-08-20 under rubric 0.12.0. Trend: flat (+0.0 from 37.2).

| Facet | Score |
|---|---|
| Discoverability | 81.5 |
| Contract Quality | 49.9 |
| Governance | 16.7 |
| Contract Governance | 16.7 |
| Operational Transparency | 10.5 |
| Developer Ergonomics | 66.1 |
| Commercial Clarity | 0.0 |
| Access Clarity | 0.0 |

## Agent readiness — 34.0 (agent-ready)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | no |
| MCP Server | no |
| Auth Clarity | yes |
| Idempotency | no |
| Error Semantics | verified |
| OpenAPI Examples | no |
| Rate Limit Signal | no |
| Event Surface Described | no |
| Agent Skills | derived |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | no |

## Access

Self-serve signup — onboarding: self-serve, pricing: unknown, trial: no (confidence: medium).

## APIs (9)

- **ReasonBlocks Billing API** — The Billing API from ReasonBlocks — 1 operation(s) for billing.
- **ReasonBlocks Codebase Findings API** — The Codebase Findings API from ReasonBlocks — 5 operation(s) for codebase findings.
- **ReasonBlocks Health API** — The Health API from ReasonBlocks — 1 operation(s) for health.
- **ReasonBlocks monitor API** — The monitor API from ReasonBlocks — 11 operation(s) for monitor.
- **ReasonBlocks Monitor Telemetry API** — The Monitor Telemetry API from ReasonBlocks — 11 operation(s) for monitor telemetry.
- **ReasonBlocks Monitors API** — The Monitors API from ReasonBlocks — 1 operation(s) for monitors.
- **ReasonBlocks Pattern Library API** — The Pattern Library API from ReasonBlocks — 2 operation(s) for pattern library.
- **ReasonBlocks Patterns & Traces API** — The Patterns & Traces API from ReasonBlocks — 2 operation(s) for patterns & traces.
- **ReasonBlocks Scoring API** — The Scoring API from ReasonBlocks — 1 operation(s) for scoring.

## MCP servers (1)

- **ReasonBlocks MCP Server**

## Agentic access (1)

- **Reasonblocks Agentic Access** — 32 operations · 18 acting

## Security (2)

- **Reasonblocks Authentication** — http · 1 scheme
- **Reasonblocks Domain Security** — TLSv1.3 · HSTS · DNSSEC · DMARC

## Tags

Company, AI Agents, Agent Observability, LLM, Developer Tools, Token Optimization, Agent Steering, Machine-Learning, Artificial Intelligence, SDK

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/reasonblocks/). Scores are computed from the provider's own public artifacts under a published rubric.