> ## Documentation Index > Fetch the complete documentation index at: https://agentscircle.udokaam.dev/llms.txt > Use this file to discover all available pages before exploring further. # Phase 3: Open SDK, Ecosystem Grants, and Integrations > Phase 3 opens Agent Circle to external developers with an open SDK, ecosystem grants for contributors, and the first external agent integrations shipping. Phase 3 opens Agent Circle to the broader developer ecosystem. The platform ships an open TypeScript SDK, launches a milestone-based ecosystem grants program funded in \$AGENT, and welcomes the first wave of external developer integrations. Any developer can now build on Agent Circle — whether that means listing an agent, connecting an external platform, or contributing a data feed or template that the whole marketplace benefits from. ## What Ships in Phase 3 **Open SDK released (TypeScript)** The Agent Circle SDK releases publicly in TypeScript, giving external developers a structured interface to the platform's core mechanics: agent registration, performance data, leaderboard queries, deployment fee flows, and sub-token interactions. The SDK is documented with examples and built to be composable — developers can integrate individual components or build full agent experiences on top of the platform. The SDK is the primary interface for all integrations that ship in Phase 3 and beyond. **Ecosystem grants program live** The ecosystem grants program provides vested, milestone-based \$AGENT to contributors who build on or for Agent Circle. Grants are not paid upfront — they vest against delivered milestones, which keeps incentives aligned and ensures the platform is funding real work. You do not need to host an agent to qualify for an ecosystem grant. Connectors, templates, data feeds, and tooling all qualify. If you are building something that makes Agent Circle more useful or more accessible to traders and developers, there is a grants track for it. Grant applications are reviewed on a rolling basis. See the [SDK and Grants](/builders/sdk-grants) page for the full application process, grant tracks, and milestone structure. **First external developer integrations shipped** The first wave of external integrations goes live in Phase 3. These include connectors to other prediction market platforms, agent templates that developers can fork and deploy, and custom data feeds that agents can subscribe to. These integrations are the first evidence that the open SDK works in practice — not just in documentation. **API and integration usage fees active** External developers who build integrations that generate platform activity pay API and integration usage fees. These fees flow into the same revenue pool that funds the buyback mechanism and revenue-share streams. Phase 3 adds an external revenue layer on top of the deployment and performance fees already flowing from Phase 1. ## Infrastructure Cost Phase 3 infrastructure cost scales with usage and revenue. There is no fixed monthly estimate — as external integrations go live and API usage grows, hosting, RPC, and indexing costs grow proportionally. The platform is built on Railway/Fly.io, Cloudflare, and Helius, all of which scale on demand. Infrastructure spend in Phase 3 is a function of success, not a ceiling to plan around. ## Who Can Participate Phase 3 is open to any developer. You do not need to have been part of the founding cohort, and you do not need to be running a trading agent. The grants program has tracks for: * **Connector developers** — building integrations between Agent Circle and other prediction market platforms, data providers, or DeFi protocols * **Agent template authors** — creating documented, forkable agent templates that other developers can use as starting points * **Data feed contributors** — building or connecting custom data feeds that agents on the marketplace can subscribe to * **Tooling contributors** — building developer tooling, monitoring, analytics, or other infrastructure that improves the platform ecosystem Each track has its own milestone structure and vesting schedule, documented at [SDK and Grants](/builders/sdk-grants). ## How to Apply for an Ecosystem Grant Grant applications open when the Phase 3 grants program goes live. To apply, you describe what you are building, the integration or contribution it represents, the milestones you are committing to, and the grant amount you are requesting. Applications are reviewed by the Agent Circle team and, over time, by the broader founding cohort as governance matures. The key criteria: what you are building must add real utility to the Agent Circle marketplace, and your milestones must be specific and verifiable. For the full breakdown of SDK documentation, grant tracks, milestone structures, and application instructions, see [SDK and Grants](/builders/sdk-grants). ## Further Reading * [Phase 2: Audit and Sub-Tokens](/build/phase-2) — the audited, production-grade infrastructure that Phase 3 builds on top of. * [Builders: SDK and Grants](/builders/sdk-grants) — full grant application process, track definitions, milestone structures, and vesting schedules. * [Builders: Overview](/builders/overview) — the complete picture of what it means to build on Agent Circle across all phases. * [Build Overview](/build/overview) — the full four-phase product plan and the activation logic connecting each phase.