GPT-5 Pro API — multimodal tool orchestrator
Run complex assistants with text, image, and speech interfaces, plus multi-step function calling for real-world automation.
Function calling
Describe tools once — GPT-5 Pro plans and executes the calls.
Realtime voice
Sub-250ms latency for live voice assistants and co-pilots.
Workflow planning
Automatically decompose requests into subtasks across tools.
Streaming responses
SSE and WebSocket streaming keep UIs responsive.
Try a prompt in seconds
Context
128K tokens
Keep transcripts, CRM notes, and policies in-session.
Tools
Salesforce, Jira, Slack
Register schema-driven tools for automated calls.
Mode
Realtime / Text
Switch between conversational voice and pure text.
Automation workflow
See the call graph, tool outputs, and user-facing summary in a single response payload.
Predictable token billing
Realtime mode adds per-second charges while sharing the same token bucket.
Start from day one with zero minimums and live usage analytics inside the dashboard.
- Latency-optimised global POP routing
- Automatic retries and circuit breaking
- Per-request billing insights in real time
Ideal for fast-growing teams that want predictable discounts and proactive quota alerts.
- Priority capacity reservations
- Team workspaces with audit trails
- Custom rate and budget controls
Tailored SLAs, private regions, and compliance workflows for regulated workloads.
- Private networking options
- Dedicated solutions engineer
- Custom invoicing and procurement
Function calling example
Create a workspace and API key
Provision long-lived or temporary keys from the Transend dashboard and configure which providers are available to your team.
Call POST /chat/gpt-5-pro
Register tool metadata and let the model orchestrate multi-step execution automatically.
Ship the result to production
Each response returns task identifiers, elapsed time, and cost metadata. Wire it into your app with webhooks, polling, or background jobs.
const res = await fetch("https://api.transendai.net/v1/chat/gpt-5-pro", {
method: "POST",
headers: {
Authorization: `Bearer ${process.env.TRANSEND_API_KEY}`,
"Content-Type": "application/json",
},
body: JSON.stringify({
model: "gpt-5-pro",
tools: [
{
name: "createTicket",
description: "Create a Jira ticket",
parameters: {
type: "object",
properties: { title: { type: "string" }, priority: { type: "string" } },
required: ["title"]
}
}
],
messages: [{ role: "user", content: "Log a Jira bug for login timeouts." }]
}),
});
console.log(await res.json());
Agentic model comparison
| Model | Context | Tool calling | Voice | Price |
|---|---|---|---|---|
| GPT-5 Pro | 128K | ✅ multi-call | Realtime | $18 / 1M |
| Claude Sonnet 4.5 | 200K | ✅ | Text | $15 / 1M |
| Gemini 2.5 Pro | 1M | ✅ | Realtime | $12 / 1M |
Automation teams choose GPT-5 Pro
Teams across finance, creative studios, and indie hackers ship production workloads with Transend AI.
“GPT-5 Pro API helped us ship a usable MVP in under a week while cutting inference spend by 30%.”
“Latency is steady, failover is automatic, and on-call runs are finally quiet again.”
Answers for builders
Didn't find what you need? Email [email protected] – we reply within 12 hours.
Which regions does the GPT-5 Pro API support?
Transend operates POPs in us-east, us-west, eu-central, and ap-southeast. The platform routes to the closest region automatically, and enterprise plans can request private regions or custom data residency.
Can we stream logs into our own observability stack?
Yes. Forward operational events through webhooks or export APIs into Datadog, Grafana, BigQuery, or any system that can ingest JSON streams.
How do we enforce budgets?
Real-time spend analytics live in the dashboard. Define model, team, or tag-based alerts and automatically throttle or downgrade when a budget threshold is reached.
Ready to ship with GPT-5 Pro API?
Deploy unified AI experiences with a single API key. No quota bureaucracy, just blazing fast inference on the models your team loves.