send_fax
shallowcom.sendthisfax/fax · Verify this server
Submit an uploaded PDF for faxing. Step 1 (before this tool): upload the PDF over plain HTTP multipart, using any HTTP client you have — shell, JavaScript fetch with FormData, Python, etc.: curl -F "file=@document.pdf" https://www.sendthisfax.com/api/upload fetch("https://www.sendthisfax.com/api/upload", {method: "POST", body: formDataWithFile}) The response contains fax_public_id and page_count. PDFs must be unencrypted, at most 50 MB and 1000 pages. Step 2: call this tool with the fax_public_id and the recipient fax number. Two modes: - With an API key (Authorization: Bearer stf_live_... on this MCP connection): the fax price is debited from the prepaid credit balance and sending starts immediately — no checkout, no browser. sender_email and billing_country are optional (they default to the key's records). Buy credits at https://www.sendthisfax.com/en/credits. - Without an API key: sender_email and billing_country are REQUIRED and the tool returns a checkout_url the USER must pay in a browser; the fax is sent automatically once paid. In both modes, poll get_fax_status until status reaches "delivered" or "failed" (failures after payment are auto-refunded). For integration testing, +19898989898 is the designated test recipient number.
1 trials · measured 8 days ago
send_fax scores 100.0/100 on Vouch's measured behaviour index, from 1 real invocation trials against com.sendthisfax/fax, measured 25 Aug 2026 under methodology v0.2.0. Every measured component scored 100.
Component breakdown
| Component | Weight | Value |
|---|---|---|
| Reliability | 35% | not applicable |
| Schema integrity | 25% | 100.0 |
| Failure behaviour | 15% | not applicable |
| Latency | 15% | not applicable |
| Concurrency | 10% | not applicable |
Tool details
- Transport
- remote
- Credential class
- self-provisionable
- Category
- Developer infrastructure
- Input schema
- not declared
- Output schema
- not declared
- Side-effect classification
- unclassified
Score history
| Day | Score | Tier | Methodology |
|---|---|---|---|
| 2026-08-25 | 100.0 | shallow | v0.2.0 |
Probe evidence
| Probe | Outcomes |
|---|---|
| schema_integrity | pass: 1 |
Raw request/response logs are not archived yet — the outcome counts above are drawn directly from every recorded trial.
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