Couryo MCP server

• Registry namecom.couryo/toolsverified in the MCP registry

The registry name sits under couryo.com. The registry only lets a publisher use that namespace after proving control of the domain through DNS or HTTP.

• Stateanswerschecked 2026-10-29
• Tools6
• Server calls itselfcouryo-free-tools
• Server version0.1.0
• Protocol version2025-06-18

On 2026-10-29 the server answered initialize and tools/list without a sign-in. First answer in 215 ms.

• Its tools do explain rejected emails from receiving servers in Portuguese, but not send transactional email through an API or SMTP.
• Checked on 6 of the 7 days it takes to judge reliability.

Said by rules from the measurements above. The likely first call is a model's pick from the tool list; read its description before relying on it.

• INITE MCP scoreafter a weeka score needs 7 daily checks: 6 so far
• What an agent can do with it1 of 2 use cases
• Answeredmeasuring6 of the 7 daily checks it takes to print a share
• Median first answer226 ms
• Space in an agent's context≈ 1,118 tokensthe definitions of all its tools (6), which an agent carries on every turn
• Tool definitionsA · 94 of 100
• Typed results0 of 6 toolsdeclared outputSchema: results come typed, read once

• Parameters without a description: in 2 of 6

A program checks the server once a day: initialize and tools/list, no model. Tokens are the definitions' length at about four characters a token. The grade averages six checks of every tool's name, description, schema and annotations; it says how well the tools are described, not whether they work. The score weighs what was measured and nothing else: answering (25%), doing the product's job (25%), definitions (20%), context (10%), use (10%) and how readily a client connects (10%). A part that was not measured is left out, and a hidden instruction caps the score at 40. The state of vendors' MCP servers: method and numbers →

• verify_email

  Checks one email address without sending anything: format, typo in big providers ("gmail.com.br" → "gmail.com", "hotmial.com"), disposable inbox, shared mailbox (contato@, sales@) and whether the domain receives email (MX). Verdict valid…

• verify_emails

  Batch of verify_email: the same checks for up to 100 addresses at once, one verdict each (valid, risky, invalid) plus the totals. Run it before a send and drop invalid and disposable addresses. Each address counts in the daily limit…

• check_domain_dns

  Checks the email setup of any domain: SPF (one record, ending, the 10 DNS lookup limit), DKIM on the common selectors (or dkim_selector), DMARC policy and reports, MX and mailbox provider, MTA-STS, TLS-RPT and BIMI. Answers a 0 to 100…

• explain_smtp_error

  Explains a bounce or SMTP error text ("550 5.7.515 Access denied", "452 4.2.2 mailbox full") in plain words: hard (the address does not work), soft (temporary) or policy (a provider rule, not the address), the provider and the next step…

• generate_spf

  Builds one SPF record (TXT at the domain) from the services that send for it: includes, IPv4 and IPv6, mx and a. Starts with ~all (softfail), the safe choice; use policy fail (-all) once every sender is listed. Remember the limit of 10…

• generate_dmarc

  Builds one DMARC record (TXT at _dmarc.<domain>). Start with policy none and a report address (rua), read the reports, then move to quarantine and reject once every legitimate sender passes SPF or DKIM aligned. Free, no network. / Monta o…

• com.couryo/mcpanswers, requires sign-inverified in the MCP registry