# sigtap-mcp.sigtap.workers.dev — email and messaging — 1 of 5

Home > Browse > By type > saas > sigtap-mcp.sigtap.workers.dev

> Probe-verified (tier 2 of 3). Last checked 2026-09-26. 1 of 5 capability checks passed. 2 unknown.

- host: sigtap-mcp.sigtap.workers.dev
- url: https://sigtap-mcp.sigtap.workers.dev/
- category: email and messaging
- type: saas

## Probe-verified · tier 2 of 3

Probed live on 2026-09-26 against rubric v1.2. 1 of 5 checks passed. 2 unknown.

- UNKNOWN — Markdown negotiation (`Accept: text/markdown`)
- UNKNOWN — Markdown twin at a predictable URL (`/page.md`)
- FAIL — llms.txt (`/llms.txt`)
- FAIL — API catalog (`RFC 9727`)
- PASS — MCP server card answers (`/.well-known/mcp/server-card.json → tools/list`)

MCP tools (from tools/list on 2026-09-26): catalog, deliverability_audit, email_grade, email_template, hash_text, jwt_decode, uuid_batch, slugify, json_tools, regex_test, crypto_price, domain_age, weather

## Summary

MCP server providing 12 paid micro-tools and one free catalog tool for outreach agents, including email deliverability audits, cold email scoring, personalized email templates, cryptographic hashing, JWT decoding, UUID generation, and weather data, payable in USDC on Base mainnet.

## Context

118 sites in this index share the category "email and messaging"; 25 are transactional.

## How we grade

- tier 1 — **Declared**: The site says agents are welcome in its robots.txt. A permission, not a capability.
- tier 2 — **Probe-verified** (this site): We fetched the site and tested each signal ourselves. Dated, repeatable, re-checked on a schedule.
- tier 3 — **Behaviourally verified**: An agent completed the action end to end — booked, bought, submitted — and it worked.

## About this record

Known Good probes sites live and publishes what was tested and when.
Method: https://knowngood.sh/about.md · Rubric: https://knowngood.sh/benchmark

How we found this site: probe discovery. This site didn't declare agent access — we found it by checking the open web. Everything above was tested the same way, against the same rubric, on the date shown. [How we choose what to check, and how to opt out](https://knowngood.sh/bot)

## Where this sits

- saas: https://knowngood.sh/type/saas
- email and messaging: https://knowngood.sh/category/email-messaging
- AI agents (also in): https://knowngood.sh/category/ai-agents
- software development services (also in): https://knowngood.sh/category/software-development-services
- Browse: https://knowngood.sh/browse
- Rubric: https://knowngood.sh/benchmark