API guide
Composio vs Arcade vs Pica AI Agent Tool API (2026)
Composio, Arcade, and Pica compared for AI agent tool APIs: SaaS coverage, auth model, tool quality, latency, and production fit.

The Tool-Use Layer Most Agent Stacks Are Missing
By 2026, the bottleneck for production AI agents is not models. It is tools. Models are smart enough; what slows teams down is wiring up Gmail, Salesforce, Linear, Notion, and Slack with auth, rate limits, schemas, and retries that do not blow up under real-world conditions.
Three platforms have emerged to solve this layer: Composio, Arcade, and Pica. They each ship hundreds of pre-built tool integrations with OAuth flows, schemas the LLM can call, and runtime infrastructure to actually execute the side effects. They are not interchangeable. This guide breaks down where each one wins.
TL;DR
- Composio has the largest catalog (250+ apps in 2026) and the deepest framework integrations (LangChain, LlamaIndex, OpenAI Agents SDK, CrewAI, Vercel AI SDK). Best when breadth matters.
- Arcade focuses on quality and security over catalog size. Their tools are hand-curated, the OAuth model is the cleanest of the three, and the developer experience treats authorization as a first-class concern.
- Pica sits closer to the data plane: it abstracts SaaS APIs as a unified data model, which is great for cross-tool queries ("find every customer mentioned in the last 30 days across HubSpot, Salesforce, and Gmail").
If you need a lot of tools fast, pick Composio. If you are running agents on behalf of paying users and security review is real, pick Arcade. If your agent is doing data work across SaaS systems, pick Pica.
Key Takeaways
- Catalog size: Composio ~250+, Pica ~150+, Arcade ~120 (curated).
- Auth model: Arcade's per-user OAuth scoping is the cleanest, Composio supports both managed and BYO OAuth, Pica handles auth via a unified connection abstraction.
- Latency overhead added on top of native APIs: Pica ~80ms, Composio ~120ms, Arcade ~150ms. None are deal-breakers.
- Pricing: All three are usage-based on tool calls; Composio has the most generous free tier; Arcade has enterprise-friendly seat-based add-ons.
- Framework lock-in: Composio is multi-framework, Arcade has its own runtime with adapters, Pica focuses on direct API calls.
Decision Table
| Need | Pick | Why |
|---|---|---|
| Maximum tool catalog | Composio | 250+ apps, fastest growing |
| Per-user OAuth security | Arcade | Best-in-class scoped auth |
| Cross-SaaS data queries | Pica | Unified data model |
| LangChain / OpenAI Agents SDK | Composio | First-class adapters |
| Audit-ready logging | Arcade | Mature audit trails |
| Ad-hoc one-off integrations | Pica | Lowest barrier per tool |
Composio
Composio's bet is that agents will use a long tail of tools, so the platform with the largest, best-maintained catalog wins. Their 250+ integrations cover the standard CRM/calendar/comms/repo set plus a long tail (Linear, Cal.com, Notion databases, Reddit, weather APIs, even browsers).
import { Composio } from "@composio/core";
import { OpenAI } from "openai";
const composio = new Composio({ apiKey: process.env.COMPOSIO_KEY });
const tools = await composio.tools.get({ user_id: "user_123", apps: ["GMAIL", "LINEAR"] });
const openai = new OpenAI();
const completion = await openai.chat.completions.create({
model: "gpt-5",
messages: [{ role: "user", content: "Summarize my unread email and file action items as Linear issues." }],
tools,
});
The framework story is what makes Composio sticky. The same tool definitions work in OpenAI Agents SDK, LangChain, LlamaIndex, CrewAI, and Vercel AI SDK with one-line adapters. If your agent stack is in flux — and in 2026, it usually is — that flexibility is worth a lot.
What is good:
- Catalog breadth. New SaaS apps land within weeks.
- Multi-framework adapters that actually feel native.
- Triggers (event-driven actions, e.g., "when a Slack message arrives, run this agent") are first-class.
What is mid:
- Tool quality varies across the long tail. Top-50 apps are well-maintained; obscure integrations sometimes lag behind upstream API changes.
- Audit logging is improving but not yet at Arcade's level.
Arcade
Arcade's pitch is the hardest to fake: tool quality and authorization rigor. Their integrations are curated, every action has explicit scopes, and the auth handshake is per-user with consent screens that match what compliance teams expect.
The Arcade runtime is also distinctive. It is not just a tool catalog — it is an execution platform that runs your tool calls on Arcade's infrastructure, with retries, idempotency, and structured logs.
from arcadepy import Arcade
client = Arcade(api_key=os.environ["ARCADE_API_KEY"])
response = client.tools.execute(
tool_name="Gmail.SendEmail",
user_id="user_123",
inputs={"to": "team@example.com", "subject": "Status", "body": "Shipping today."},
)
What is good:
- Per-user OAuth scoping that maps to real consent. If your agent is acting on behalf of customers, this is the right model.
- Tool quality is uniform — Arcade's bar means fewer surprises.
- Strong audit trails: every tool call is logged with inputs, outputs, user, scope, and timestamp.
What is mid:
- Smaller catalog than Composio. If you need an integration with a niche SaaS, you may have to build it yourself.
- The runtime adds a tiny bit of latency that matters in tight conversation loops.
Pica
Pica thinks differently about the problem. Instead of treating each SaaS API as a separate tool, they expose a unified data model on top: customers, deals, messages, files. An agent asks for "all customers updated in the last week" and Pica fans out across HubSpot, Salesforce, Pipedrive, etc., normalizing the schema.
import { Pica } from "@picahq/sdk";
const pica = new Pica(process.env.PICA_SECRET);
const customers = await pica.unified.crm.contacts.list({
connections: ["hubspot", "salesforce"],
updated_after: new Date(Date.now() - 7 * 24 * 60 * 60 * 1000),
});
This makes Pica unusually good for the data-plane use case: agents that read across SaaS systems and synthesize. It is less natural for write-heavy agents that need to use a specific API surface (e.g., create a particular Notion block type) — for those, Composio or Arcade map more directly to the underlying API.
What is good:
- Cross-tool queries that would otherwise require N adapters and a data model of your own.
- Lowest latency overhead of the three for read-heavy workloads.
- Direct passthrough mode lets you fall back to the native API when the unified model doesn't cover a feature.
What is mid:
- Smaller catalog and shallower coverage of write actions in some long-tail apps.
- The unified model is opinionated; if your agent needs a SaaS-specific feature, expect to drop to passthrough.
Pricing Reality
All three are tool-call metered, with free tiers in the 1k–5k call range. At 100k tool calls/month:
- Composio: usually the cheapest at scale.
- Pica: middle, with a discount on read-heavy unified queries.
- Arcade: highest sticker, but enterprise plans bundle audit/SSO that the others charge separately for.
Run your real workload against all three free tiers before committing.
Who Should Choose What
- Pick Composio if your agent needs a wide range of SaaS integrations and you want flexibility across frameworks.
- Pick Arcade if you are running agents on behalf of paying customers and per-user OAuth, audit, and tool quality matter more than catalog breadth.
- Pick Pica if your agent's primary job is reading across SaaS systems and presenting a unified view.
The Verdict
These three platforms are converging on the same problem from different angles. In 2026, most production agent teams end up using two: typically Composio for breadth and Arcade for the high-stakes user-acting-on-behalf flows. Pica is a third tool when you have data-plane work, not a replacement for the others.
Related reading: Best AI agent APIs for the broader landscape, and LangChain vs CrewAI vs OpenAI Agents SDK for the framework you'll plug these into.
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