For Agents
Convert text or SSML into spoken audio across multiple voices and languages, and manage pronunciation lexicons through Amazon Polly.
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Amazon Polly, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
# On the machine that will host your Jentic One instance:
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
What an agent can do with Amazon Polly API.
Synthesize plain text or SSML input into MP3, OGG, or PCM audio with SynthesizeSpeech
Generate speech-mark JSON aligned to sentence, word, viseme, or SSML boundaries for lipsync and captions
Run long-form synthesis tasks that write multi-megabyte audio output to an S3 bucket asynchronously
List available voices filtered by language code, gender, or supported engine (neural, generative)
GET STARTED
Use for: I need to convert a paragraph of text to speech, Generate spoken audio in a neural voice for a notification, List all available Polly voices for British English, Start a long-form synthesis task that writes the result to S3
Not supported: Does not transcribe audio, translate text, or analyze speech content — use for text-to-speech synthesis and pronunciation-lexicon management only.
Jentic publishes the only available OpenAPI document for Amazon Polly, keeping it validated and agent-ready.
Jentic publishes the only available OpenAPI specification for Amazon Polly, keeping it validated and agent-ready. Amazon Polly is a managed text-to-speech service that turns text into lifelike audio across dozens of voices, languages, and speech engines (standard, neural, long-form, and generative). The API exposes synchronous synthesis via SynthesizeSpeech for short clips, asynchronous synthesis tasks for long-form audio written to S3, and pronunciation lexicon management for fine-grained word-level control. It supports plain text and SSML input and returns MP3, OGG Vorbis, PCM, or JSON speech-mark output.
Upload pronunciation lexicons in PLS format and apply them per request to override word pronunciations
Track and retrieve completed or failed synthesis tasks by TaskId for batch audio production
Patterns agents use Amazon Polly API for, with concrete tasks.
★ On-Demand Voice Notifications
Convert short alerts and IVR prompts to speech in real time. SynthesizeSpeech accepts up to a few thousand characters of plain text or SSML, a VoiceId, an Engine (standard, neural, generative), and an OutputFormat, and returns the audio bytes synchronously. Useful for chatbots that need a low-latency spoken response or contact-center prompts generated on the fly.
Call POST /v1/speech with Text 'Your order has shipped', VoiceId 'Joanna', Engine 'neural', and OutputFormat 'mp3'
Long-Form Audiobook Production
Produce multi-minute or multi-hour narrated audio asynchronously by starting a SpeechSynthesisTask. The task writes the output (MP3 or OGG) to a configurable S3 bucket and prefix, with optional speech marks for chapter and word alignment. Generative and long-form engines maintain a coherent, natural prosody across long passages where SynthesizeSpeech would hit character limits.
Call POST /v1/synthesisTasks with OutputS3BucketName 'my-audio', VoiceId 'Ruth', Engine 'long-form', Text containing the chapter, and OutputFormat 'mp3'
Custom Pronunciations with Lexicons
Override default pronunciations of brand names, drug names, or technical terms by uploading a PLS pronunciation lexicon. PutLexicon stores the lexicon under a name, and each SynthesizeSpeech call lists which lexicons to apply. Pairs well with neural voices for consistent product-name pronunciation across an audio library.
Call PUT /v1/lexicons/{LexiconName} 'brand-names' with the PLS XML, then call POST /v1/speech with LexiconNames ['brand-names'] and the source text
AI Agent Voice Output via Jentic
A voice-first agent uses Jentic to discover Polly's SynthesizeSpeech operation, load its schema, and convert each generated response to audio for playback. Jentic stores AWS credentials in its vault and signs every call with SigV4, so the agent only handles the response text and the resulting audio bytes.
Use Jentic to search 'convert text to speech with a neural voice', load SynthesizeSpeech, and execute it with the agent's response text
9 endpoints — jentic publishes the only available openapi specification for amazon polly, keeping it validated and agent-ready.
METHOD
PATH
DESCRIPTION
/v1/speech
Synchronously synthesize text or SSML to audio
/v1/synthesisTasks
Start an asynchronous long-form synthesis task writing to S3
/v1/synthesisTasks/{TaskId}
Get the status and output URI of a synthesis task
/v1/voices
List available voices filtered by language and engine
/v1/lexicons/{LexiconName}
Upload or replace a pronunciation lexicon
/v1/lexicons
List stored pronunciation lexicons
/v1/speech
Synchronously synthesize text or SSML to audio
/v1/synthesisTasks
Start an asynchronous long-form synthesis task writing to S3
/v1/synthesisTasks/{TaskId}
Get the status and output URI of a synthesis task
/v1/voices
List available voices filtered by language and engine
/v1/lexicons/{LexiconName}
Upload or replace a pronunciation lexicon
Three things that make agents converge on Jentic-routed access.
Credential isolation
AWS access keys are stored encrypted in the Jentic vault. SigV4 signatures are computed per request, so agents never hold the raw secret access key.
Intent-based discovery
Agents search by intent (e.g., 'convert text to speech with a neural voice') and Jentic returns SynthesizeSpeech with its input schema and accepted VoiceIds and Engines.
Time to first call
Direct integration: half a day to a day for SDK wiring, IAM scoping, and SigV4 signing. Through Jentic: under 30 minutes — search, load schema, execute.
Alternatives and complements available in the Jentic catalogue.
Amazon Transcribe
Transcribe inverts Polly: speech-to-text for inbound audio while Polly handles text-to-speech for outbound audio
Use Transcribe when the agent needs to convert user audio into text; use Polly when the agent must speak responses back.
Amazon Comprehend
Detect language and sentiment in source text before choosing a Polly voice and engine
Use Comprehend when the agent needs to pick the correct LanguageCode for Polly based on detected source-text language.
Amazon Rekognition
Combine vision analysis with Polly narration to produce described-audio for image and video content
Use Rekognition for image or video understanding, then pipe the description into Polly to generate spoken narration.
Specific to using Amazon Polly API through Jentic.
Why is there no official OpenAPI spec for Amazon Polly?
AWS does not publish an OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call Amazon Polly via structured tooling. It is validated against the live API and kept up to date. Get started at https://app.jentic.com/sign-up.
What authentication does the Amazon Polly API use?
Polly uses AWS SigV4 HMAC request signing with an AWS access key ID and secret. Through Jentic, AWS credentials live in the vault and SigV4 signatures are produced per request so the agent never sees raw secrets.
Can I generate long audio files like audiobooks?
Yes. Use POST /v1/synthesisTasks for asynchronous synthesis: Polly writes the full audio to your specified S3 bucket. SynthesizeSpeech (POST /v1/speech) is limited to shorter inputs and returns audio synchronously.
Which voice engines does Polly support?
Polly supports the standard, neural, long-form, and generative engines. Engine availability varies by voice; call GET /v1/voices and inspect SupportedEngines on each Voice to pick one compatible with your VoiceId.
What are the rate limits for Polly?
Polly enforces per-region transactions-per-second limits per engine; neural and generative engines have lower default TPS than standard. Throttled requests return ThrottlingException — back off and retry, or request a quota increase via Service Quotas.
How do I synthesize speech through Jentic?
Search Jentic for 'convert text to speech with a neural voice', load SynthesizeSpeech, and execute it with Text, VoiceId, and Engine. Install with pip install jentic; AWS credentials come from the Jentic vault.
/v1/lexicons
List stored pronunciation lexicons