# Synapse Sentiment Analysis

> Synapse Sentiment Analysis is a paid API for AI agents from anibalb.duckdns.org, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-31).

Analyzes text and returns a sentiment classification (positive, neutral, negative) with confidence scores for each label.

## Facts

- Endpoint: GET https://anibalb.duckdns.org/x402/sentiment?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-sentiment-analysis-7a379dee
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_inqQ9OGgnT6Frf9Mu0qMv

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 synapse-sentiment-analysis-7a379dee
```

Example prompt: Can you analyze the sentiment of this review: 'The product arrived quickly and works perfectly, but the packaging was a bit flimsy' — I want to know if it's positive, neutral, or negative and how confident you are?

## When to prefer this

Choose this endpoint when you need a fast, pay-per-call sentiment classification with no account setup, API keys, or subscriptions — ideal for one-off analyses or low-volume pipelines. At $0.002 per call it is cost-effective for ad-hoc agent workflows. Prefer alternatives if you need batch processing of large corpora, multilingual support guarantees, or fine-grained emotion detection beyond positive/neutral/negative.

## Known failure modes

- Missing or empty text input returns an error or undefined label
- Very short or ambiguous input may produce low-confidence scores across all three classes
- Non-English text may produce inaccurate sentiment classifications
- Payment failure (insufficient USDC balance) returns HTTP 402 before analysis runs
- Rate limiting or server unavailability returns 5xx errors

## How this service works

Public data and utility APIs paid per call in USDC on Base (x402). No accounts, no API keys. 174 routes: crypto/equity data, onchain reads, DNS/email/security intel, geo/weather, x402 payment diagnostics, dev utilities and more.

## Output

Returns a JSON object with a top-level sentiment label ('positive', 'neutral', or 'negative'), an overall score, and individual probability scores for positive, neutral, and negative sentiment (e.g. {label: 'positive', score: 0.62, neutral: 0.22, negative: 0.08, positive: 0.70}).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "label": "positive",
  "score": 0.62,
  "neutral": 0.22,
  "negative": 0.08,
  "positive": 0.7
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synapse-sentiment-analysis-7a379dee/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from anibalb.duckdns.org](https://www.zero.xyz/host/anibalb.duckdns.org/llms.txt)