CSTM-2 Developer API

Authorization: Bearer cstm_lm_Kx9mPqR8vT2nLsY5wBrD7...

{
  "code": "WRONG_MODEL_KEY",
  "message": "This endpoint requires a careervision key (prefix: cstm_vi_)"
}

cstm_lm_Kx9mPqR8vT2nLsY5wBrD7hJcF1eNgA0iUoXvQz
│       │  └─── random 32-char base-58 token (cryptographically secure)
│       └────── model family identifier
└────────────── CSTM-2 platform prefix

  cstm_lm_  →  CareerLM        cstm_vc_  →  CareerVoice
  cstm_vi_  →  CareerVision    cstm_em_  →  CareerEmbed
  cstm_ag_  →  CareerAgent     cstm_sc_  →  CareerScore
  cstm_wb_  →  CareerWebAPI

Authorization: Bearer cstm_lm_YOUR_KEY    ← model-specific key
Content-Type:  application/json

Optional:
X-Request-ID:   your-trace-id            ← echoed back for tracing
X-End-User-ID:  user-123                 ← per-user rate limit attribution

X-RateLimit-Limit:       60
X-RateLimit-Remaining:   47
X-RateLimit-Reset:       1720000060   ← Unix timestamp when window resets
X-CareerStudio-Model:    careerlm
X-Request-ID:            req_abc123

async function callWithRetry(fn, maxRetries = 4) {
  for (let i = 0; i < maxRetries; i++) {
    try { return await fn(); }
    catch (err) {
      if (err.status !== 429) throw err;
      const reset = err.headers?.get('x-ratelimit-reset');
      const wait  = reset ? Math.max(0, Number(reset) * 1000 - Date.now()) : (2 ** i) * 1000;
      await new Promise(r => setTimeout(r, wait));
    }
  }
  throw new Error('Max retries exceeded');
}

const res = await fetch('/api/cstm2/v1/careerlm/chat/stream', {
  method:  'POST',
  headers: { Authorization: 'Bearer cstm_lm_YOUR_KEY', 'Content-Type': 'application/json' },
  body:    JSON.stringify({ messages: [{ role: 'user', content: 'Write a cover letter' }] }),
});
const reader = res.body.getReader(), dec = new TextDecoder();
while (true) {
  const { value, done } = await reader.read();
  if (done) break;
  for (const line of dec.decode(value).split('\n')) {
    if (!line.startsWith('data:') || line === 'data: [DONE]') continue;
    const chunk = JSON.parse(line.slice(6));
    process.stdout.write(chunk.choices?.[0]?.delta?.content ?? '');
  }
}

X-RateLimit-Limit:     60
X-RateLimit-Remaining: 47
X-RateLimit-Reset:     1720000060

CareerStudio-Signature: t=1720000060,v1=5257a869559d4...

const crypto = require('crypto');

function verifyWebhook(payload, signature, secret) {
  const [tPart, vPart] = signature.split(',');
  const t  = tPart.replace('t=', '');
  const v1 = vPart.replace('v1=', '');
  const expected = crypto
    .createHmac('sha256', secret)
    .update(`${t}.${JSON.stringify(payload)}`)
    .digest('hex');
  return crypto.timingSafeEqual(
    Buffer.from(v1, 'hex'),
    Buffer.from(expected, 'hex')
  );
}

npm install openai        # OpenAI-compatible SDK (recommended)
# or: yarn add openai
# or: pnpm add openai

import OpenAI from 'openai';

const client = new OpenAI({
  apiKey:  'cstm_lm_YOUR_KEY',
  baseURL: 'https://api.careerstudiomax.com/api/cstm2/v1/careerlm',
});

const res = await client.chat.completions.create({
  model:    'careerlm-large',
  messages: [{ role: 'user', content: 'Write a cover letter for a Senior PM role' }],
});
console.log(res.choices[0].message.content);

pip install openai          # OpenAI-compatible SDK
# or: pip install requests  # raw HTTP

from openai import OpenAI

client = OpenAI(
    api_key  = "cstm_lm_YOUR_KEY",
    base_url = "https://api.careerstudiomax.com/api/cstm2/v1/careerlm",
)
res = client.chat.completions.create(
    model    = "careerlm-large",
    messages = [{"role":"user","content":"Write a cover letter for a Senior PM role"}],
)
print(res.choices[0].message.content)

go get github.com/openai/openai-go      # OpenAI-compatible Go SDK
# or use net/http directly — no external dependency needed

gem 'ruby-openai'          # OpenAI-compatible
# or: gem 'faraday'         # raw HTTP

require 'openai'

client = OpenAI::Client.new(
  access_token: 'cstm_lm_YOUR_KEY',
  uri_base:     'https://api.careerstudiomax.com/api/cstm2/v1/careerlm'
)
resp = client.chat(
  parameters: { model: 'careerlm-large', messages: [{ role: 'user', content: 'Write a cover letter' }] }
)
puts resp.dig('choices', 0, 'message', 'content')

composer require openai-php/client   # OpenAI-compatible
# or: composer require guzzlehttp/guzzle  # raw HTTP

use OpenAI;
$client = OpenAI::factory()
    ->withApiKey('cstm_lm_YOUR_KEY')
    ->withBaseUri('https://api.careerstudiomax.com/api/cstm2/v1/careerlm')
    ->make();

$result = $client->chat()->create([
    'model'    => 'careerlm-large',
    'messages' => [['role' => 'user', 'content' => 'Write a cover letter']],
]);
echo $result->choices[0]->message->content;

<!-- Maven pom.xml -->
<dependency>
  <groupId>com.squareup.okhttp3</groupId>
  <artifactId>okhttp</artifactId>
  <version>4.12.0</version>
</dependency>

// Gradle build.gradle
implementation 'com.squareup.okhttp3:okhttp:4.12.0'

[dependencies]
reqwest  = { version = "0.12", features = ["json"] }
tokio    = { version = "1", features = ["full"] }
serde    = { version = "1", features = ["derive"] }
serde_json = "1"

dotnet add package OpenAI        # OpenAI-compatible .NET SDK
# or use System.Net.Http.HttpClient directly — built-in

// Uses URLSession — no external package required
// For OpenAI-compatible SDK:
.package(url: "https://github.com/MacPaw/OpenAI.git", from: "0.3.0")

implementation("com.squareup.okhttp3:okhttp:4.12.0")
implementation("org.json:json:20240303")

dependencies:
  http: ^1.2.0        # native HTTP client — no bloat

defp deps do
  [{:req, "~> 0.5"}]   # modern HTTP client with JSON built-in
end

# Linux/macOS — usually pre-installed
brew install curl jq      # macOS (Homebrew)
apt-get install curl jq   # Debian/Ubuntu

# PowerShell 7+ (pwsh) — Invoke-RestMethod is built-in, no install needed
# Install PowerShell 7: https://aka.ms/pscore6