Overview

MisarBlog's text-to-speech (TTS) system converts article content to MP3 audio. The API works on a chunk-based model — the client splits the article into text segments, requests audio for each chunk, and the player assembles them in sequence. Chunks are cached server-side for 24 hours.

The TTS player in the MisarBlog dashboard handles chunking automatically. Use this API directly if you're building a custom reader or audio player for MisarBlog content.

Generate Audio Chunk

POST api.misar.io/blog/tts

Converts a single text chunk to MP3 audio. Returns cached audio if the chunk has been generated before.

No API key authentication is required, but the endpoint is rate-limited by IP (60 requests per minute).

Request Body

{
  "articleId": "550e8400-e29b-41d4-a716-446655440000",
  "contentHash": "a1b2c3d4",
  "chunkIndex": 0,
  "text": "Welcome to my first article. This is the opening paragraph of the article content."
}

articleIdstringrequired

UUID of the article this chunk belongs to. Used as part of the cache key.

contentHashstringrequired

Short hex hash of the article's full content (6–16 hex characters). Used as a cache-bust key — when article content changes, a new hash invalidates the old audio.

chunkIndexnumberrequired

Zero-based index of this chunk in the article sequence (0–199).

textstringrequired

The text to synthesize for this chunk. Maximum ~4000 characters per chunk.

Response

200 OK — Content-Type: audio/mpeg

Binary MP3 audio data.

Response Header	Value	Description
`Content-Type`	`audio/mpeg`	Audio format
`Cache-Control`	`private, max-age=86400`	24-hour browser cache
`X-Cache`	`HIT` or `MISS`	Whether audio was served from cache

Rate Limits

Tier	Limit
All	60 requests per 60 seconds per IP

Example

async function playArticleAudio(articleId: string, chunks: string[], contentHash: string) {
  const audioContext = new AudioContext();

  for (let i = 0; i < chunks.length; i++) {
    const res = await fetch("https://api.misar.io/blog/tts", {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({
        articleId,
        contentHash,
        chunkIndex: i,
        text: chunks[i],
      }),
    });

    if (!res.ok) {
      console.error(`Chunk ${i} failed:`, res.status);
      continue;
    }

    const arrayBuffer = await res.arrayBuffer();
    const audioBuffer = await audioContext.decodeAudioData(arrayBuffer);
    const source = audioContext.createBufferSource();
    source.buffer = audioBuffer;
    source.connect(audioContext.destination);
    source.start();

    // wait for this chunk to finish before playing the next
    await new Promise<void>((resolve) => {
      source.onended = () => resolve();
    });
  }
}

Chunk size limit

Each text chunk must be under ~4000 characters. Split article content at sentence boundaries to keep chunks within this limit and ensure natural-sounding audio.