# Telnyx Inference – GLM-5.2 Chat Completions (Large Context / Upto Tier)

> Telnyx Inference – GLM-5.2 Chat Completions (Large Context / Upto Tier) is a paid API for AI agents from x402.telnyx.com, paid per call via x402, $0.102602/call, status unknown (last checked 2026-10-15).

OpenAI-compatible chat completions using zai-org/GLM-5.2 at the large-context 'upto' pricing tier, supporting up to 200K character messages and tool use, paid per call via x402.

## Facts

- Endpoint: POST https://x402.telnyx.com/v1/chat/completions/_t/glm-5.2/upto?utm_source=zero.xyz
- Price: $0.102602/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/telnyx-inference-glm-5-2-chat-completions-large-context-upto-tier-b4a54b5a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_wpM9G9kgiNEpkKdBphQ28

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability telnyx-inference-glm-5-2-chat-completions-large-context-upto-tier-b4a54b5a -d '<json body>'
```

Example prompt: Send this 50-page contract text to GLM-5.2 and ask it to summarize the key obligations and flag any unusual clauses — use the large-context tier and allow up to 4096 output tokens.

## When to prefer this

Choose this endpoint when you need GLM-5.2 specifically at the large-context pricing tier — ideal for prompts or conversation histories with very long content (up to 200K characters per message) that exceed cheaper tier limits, or when you need per-call x402 micropayment billing without API key subscriptions. Prefer over the standard GLM-5.2 tier when document or context size is the primary constraint.

## Known failure modes

- Payment failure or insufficient USDC balance (402 error)
- Messages array exceeds 32 items or content exceeds 200K characters (422/400 validation error)
- max_tokens exceeds 8192 (validation error)
- Model temporarily unavailable or inference timeout (503/504)
- Malformed message roles or missing required fields (400 error)

## How this service works

Chat completions via Telnyx Inference (zai-org/GLM-5.2). OpenAI-compatible. $0.037526 USDC per call. (upto metered — large context)

## Output

Returns an OpenAI-compatible chat completion JSON object containing the generated assistant message (or tool call), finish reason, token usage statistics, and model identifier.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "n": {
   "type": "integer",
   "const": 1,
   "description": "Fixed to one completion per paid call."
  },
  "model": {
   "type": "string",
   "const": "zai-org/GLM-5.2",
   "description": "Model identifier; fixed to zai-org/GLM-5.2 on this route."
  },
  "tools": {
   "type": "array",
   "items": {
    "type": "object"
   },
   "maxItems": 16
  },
  "messages": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "role",
     "content"
    ],
    "properties": {
     "role": {
      "enum": [
       "system",
       "user",
       "assistant",
       "tool"
      ],
      "type": "string"
     },
     "content": {
      "type": "string",
      "maxLength": 200000
     }
    }
   },
   "maxItems": 32,
   "description": "OpenAI-style chat messages."
  },
  "max_tokens": {
   "type": "integer",
   "maximum": 8192,
   "minimum": 1
  },
  "temperature": {
   "type": "number",
   "maximum": 2,
   "minimum": 0
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/telnyx-inference-glm-5-2-chat-completions-large-context-upto-tier-b4a54b5a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.telnyx.com](https://www.zero.xyz/host/x402.telnyx.com/llms.txt)