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io.github.celfons/kyb-brasil

REMOTE · KYB-BR-AGENTS.MARCELFONS.WORKERS.DEV

Brazilian KYB beyond registry checks: CGU sanctions, forced labour, PGFN, IBAMA, signed risk score

69 Trust /100

Last scanned (14 hours ago)

Scores higher than 59% of remote servers

Reachable. Last reached 18 Oct 2026.

Category Security

Trust breakdown (7 categories)

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →

Endpoint Security63
Transport & Reachability100
Schema Quality & AI Usability73
  • AI-judged instruction clarity (excellent).Pass
  • Context-footprint check failed: tool/resource definitions use about 1526 tokens (~138/item across 11 items; 11 tools + 0 resources), over budget; trim descriptions and params. See how to fix → Fail
  • Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management20
  • Stability observed for 6 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
  • 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
  • 100% of tool parameters carry a description.Pass
  • Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Tool Safety100
  • No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
  • We read all 11 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
  • An AI judge read all 11 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
  • Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
Changelog

Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.

  • 17 Oct 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 13 to 17. That category is still filling its 30-day observation window: 4 days of observed history at the previous scan, 5 at this one. The score rises as the window fills, whether or not the server changes.

  • 15 Oct 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 7 to 10. That category is still filling its 30-day observation window: 2 days of observed history at the previous scan, 3 at this one. The score rises as the window fills, whether or not the server changes.

  • 13 Oct 26 +1
    • Stability: unverified → 0.03 ▲ functional
  • 12 Oct 26 66

    First indexed and scored.

Diagnostics

Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.

Captured 18 Oct 2026 · Probed https://kyb-br-agents.marcelfons.workers.dev/mcp

TLS valid

Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .

Subject Issuer Valid from Valid until Key Signature Serial
CN=marcelfons.workers.dev CN=YE2,O=Let's Encrypt,C=US 14 Sept 2026 13 Dec 2026 ECDSA 256 ECDSA-SHA384 6a804eccbbd98862f505bf7bf3a564903e9
SANs: *.marcelfons.workers.dev, marcelfons.workers.dev
CN=YE2,O=Let's Encrypt,C=US (CA) CN=Root YE,O=ISRG,C=US 3 Sept 2025 2 Sept 2028 ECDSA 384 ECDSA-SHA384 4df3b15dd6c0784c507cd37b58e6f115
CN=Root YE,O=ISRG,C=US (CA) CN=ISRG Root X2,O=Internet Security Research Group,C=US 13 May 2026 2 Sept 2032 ECDSA 384 ECDSA-SHA384 872165fc34b6e5fba8add5b3705fb53a
CN=ISRG Root X2,O=Internet Security Research Group,C=US (CA) CN=ISRG Root X1,O=Internet Security Research Group,C=US 13 May 2026 2 Sept 2032 ECDSA 384 SHA256-RSA 6c8f1dc727c7117f7baf853ac980f9cd

Background: What to check on a remote MCP endpoint →

DNSSEC insecure

Validation of kyb-br-agents.marcelfons.workers.dev. — Not signed

Zone DS Keys Algorithms Outcome
. trust_anchor 20326, 38696 8, 8 Verified
dev. present 60074 8 Verified
workers.dev. absent Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation
Authentication No authorisation required

The endpoint answered without asking for a token. Anyone who knows the URL can reach it.

Result No authorisation required
HTTP status 200

Background: How OAuth 2.1 works in the 2026 MCP spec →

Transports 2 probes
Transport URL Outcome Status Location
streamable-http https://kyb-br-agents.marcelfons.workers.dev/mcp Verified 200
http (plaintext) http://kyb-br-agents.marcelfons.workers.dev/mcp Inconclusive 406
MCP tools · 11 exposed · ~1,526 tokens

The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →

Tool Tokens
br_about ~75

Free. What KYB Brasil is and why to use it over a plain registry check: every tool with price and HTTP route, how x402 payment works, free-tier limits, the attestation key, docs (OpenAPI, llms.txt, skill.md) and sources. Call it first when you do not know the service.

Input schema present but exposes no named parameters.

NameTypeReqDescription
servicestringyes–
toolsarrayyes–
versionstringyes–
why_this_onearrayyes–

No examples provided.

br_batch_dossier ~96

Up to 10 CNPJs in one paid call (one payment, a third off): br_company_dossier for each. Per-item errors are reported inline in results[]; the call fails (and is not charged) only when no item succeeds. Signed answer (Ed25519 attestation), verifiable at /v1/verify.

NameTypeReqDescription
cnpjsarrayyes1 to 10 CNPJs.
NameTypeReqDescription
cachedbooleanyes–
countnumberyes–
data_freshnessstringyes–
failednumberyes–
generated_atstringyes–
receiptobject–Re-read this answer free for 10 minutes with br_replay.
resultsarrayyes–
sourcesarrayyes–
succeedednumberyes–
summaryobjectyesShort summary in English and Portuguese.

No examples provided.

br_batch_sanctions ~99

Up to 10 CNPJs in one paid call (one payment, 25% off): br_sanctions_screen for each. Per-item errors are reported inline in results[]; the call fails (and is not charged) only when no item succeeds. Signed answer (Ed25519 attestation), verifiable at /v1/verify.

NameTypeReqDescription
cnpjsarrayyes1 to 10 CNPJs.
NameTypeReqDescription
cachedbooleanyes–
countnumberyes–
data_freshnessstringyes–
failednumberyes–
generated_atstringyes–
receiptobject–Re-read this answer free for 10 minutes with br_replay.
resultsarrayyes–
sourcesarrayyes–
succeedednumberyes–
summaryobjectyesShort summary in English and Portuguese.

No examples provided.

br_company_check ~110

Free. Brazilian company (CNPJ) registration check at the Receita Federal: status (ATIVA/BAIXADA/INAPTA...), legal name, CNAE, size, age, normalized address. Structured JSON plus a summary in English and Portuguese, with sources[] and data_freshness. Rate limited (50/day).

NameTypeReqDescription
cnpjstringyesBrazilian CNPJ, 14 characters, with or without punctuation (e.g. 00.000.000/0001-91).
NameTypeReqDescription
addressobjectyes–
cachedbooleanyes–
cnpjstringyesNormalized 14-character CNPJ.
data_freshnessstringyes–
generated_atstringyes–
legal_namestringyes–
main_activity–yes–
opened_atstring|nullyes–
registration_statusstringyesATIVA, SUSPENSA, INAPTA, BAIXADA, NULA or UNKNOWN.
sourcesarrayyesSource URL and fetch time of each fact.
summaryobjectyesShort summary in English and Portuguese.

No examples provided.

br_company_count ~186

Free. How many ACTIVE Brazilian establishments match a prospecting filter (CNAE code or prefix, state/UF, city, opening date range, headquarters only), from the Receita Federal monthly registry. Use it to budget pages before paying for br_company_list. Rate limited (50/day).

NameTypeReqDescription
citystring–Municipality name (accents and case ignored).
cnaestring–CNAE code or prefix: '6201-5/00', '6201500', '6201' (class) or '62' (division).
hq_onlyboolean–Only headquarters (one row per company).
opened_afterstring–Opened on or after (YYYY-MM-DD).
opened_beforestring–Opened on or before (YYYY-MM-DD).
statestring–UF, e.g. 'SP'.
NameTypeReqDescription
cachedbooleanyes–
data_freshnessstringyes–
filtersobjectyes–
generated_atstringyes–
pages_of_100numberyes–
reference_monthstringyes–
sourcesarrayyes–
summaryobjectyesShort summary in English and Portuguese.
totalnumberyes–

No examples provided.

br_company_dossier ~163

One-call KYB due diligence, beyond a registry check: Receita Federal registration + ownership (no personal IDs) + economic group + sanctions (CEIS/CNEP/CEPIM/leniency/forced labour) + PGFN debt and fiscal regularity + IBAMA embargoes + court cases (DJEN) + federal contracts + BNDES + OFAC/UN/EU screening + gazettes + 0-100 risk score with explained red flags + per-section data quality, sources[]. Signed answer (Ed25519 attestation), verifiable at /v1/verify.

NameTypeReqDescription
cnpjstringyesBrazilian CNPJ, 14 characters, with or without punctuation (e.g. 00.000.000/0001-91).
NameTypeReqDescription
attestationobject–Ed25519 signature of this answer; verify at verify_url or with the public key at /.well-known/kyb-attestation.json.
bndes_financing–yes–
cachedbooleanyes–
cnpjstringyesNormalized 14-character CNPJ.
companyobjectyes–
data_freshnessstringyes–
data_qualityarrayyesPer-section data age: fresh, aging, stale, unavailable or unknown.
economic_group–yesOther active companies sharing a partner, with their sanction/embargo flags (null = registry unavailable).
environmental_embargoes–yesIBAMA embargo terms.
federal_contracts–yes–
federal_debt–yesPGFN active federal debt (null = dataset unavailable).
fiscal_regularityobjectyes–
gazette_mentions–yesQuerido Diário mentions in municipal official gazettes.
generated_atstringyes–
international_sanctions–yesOFAC/UN/EU name-only matches; informational, never scored.
partnersarrayyes–
receiptobject–Re-read this answer free for 10 minutes with br_replay.
riskobjectyes–
sanctions–yes–
sourcesarrayyesSource URL and fetch time of each fact.
summaryobjectyesShort summary in English and Portuguese.
warningsarrayyes–

No examples provided.

br_company_list ~242

Prospecting list: one page of 100 ACTIVE Brazilian establishments matching a filter (CNAE code or prefix, state/UF, city, opening date range, headquarters only), with CNPJ, legal and trade name, city/state, main activity and opening date. Stable paging by CNPJ; total and next_page included. Source: Receita Federal monthly registry; MEI owners' CPFs masked. Signed answer (Ed25519 attestation), verifiable at /v1/verify.

NameTypeReqDescription
citystring–Municipality name (accents and case ignored).
cnaestring–CNAE code or prefix: '6201-5/00', '6201500', '6201' (class) or '62' (division).
hq_onlyboolean–Only headquarters (one row per company).
opened_afterstring–Opened on or after (YYYY-MM-DD).
opened_beforestring–Opened on or before (YYYY-MM-DD).
pageinteger–Page of 100, default 1.
statestring–UF, e.g. 'SP'.
NameTypeReqDescription
attestationobject–Ed25519 signature of this answer; verify at verify_url or with the public key at /.well-known/kyb-attestation.json.
cachedbooleanyes–
data_freshnessstringyes–
filtersobjectyes–
generated_atstringyes–
next_pagenumber|nullyes–
pagenumberyes–
page_sizenumberyes–
receiptobject–Re-read this answer free for 10 minutes with br_replay.
reference_monthstringyes–
resultsarrayyes–
sourcesarrayyes–
summaryobjectyesShort summary in English and Portuguese.
totalnumberyes–
total_pagesnumberyes–

No examples provided.

br_company_search ~150

Free. Find a Brazilian company's CNPJ by name (legal or trade name, optional state/UF) in the Receita Federal registry of ACTIVE establishments (monthly dump; individual entrepreneurs/MEI not indexed, query those by CNPJ). Returns up to 20 candidates with CNPJ, names, city/state, main activity and opening date. Use the CNPJ with the other tools. Rate limited (50/day).

NameTypeReqDescription
limitinteger–Max results, default 10.
querystringyesCompany name, legal or trade (e.g. 'Petrobras', 'construtora alfa').
statestring–Optional UF to narrow down (e.g. 'SP').
NameTypeReqDescription
cachedbooleanyes–
data_freshnessstringyes–
generated_atstringyes–
querystringyes–
reference_monthstringyes–
resultsarrayyes–
sourcesarrayyes–
statestring|nullyes–
summaryobjectyesShort summary in English and Portuguese.

No examples provided.

br_replay ~73

Free. Fetch again, without paying, a paid answer from the last 10 minutes using the receipt.replay_token it carried. Use it when the first response was lost (timeout, disconnect) instead of paying twice.

NameTypeReqDescription
tokenstringyesreceipt.replay_token from a paid answer (valid 10 minutes).
NameTypeReqDescription
attestationobject–Ed25519 signature of this answer; verify at verify_url or with the public key at /.well-known/kyb-attestation.json.
cachedbooleanyes–
generated_atstringyes–
receiptobjectyesRe-read this answer free for 10 minutes with br_replay.

No examples provided.

br_risk_screen ~172

Red flags a registry check misses, a third of the dossier price: Receita Federal status + sanctions (CEIS/CNEP/CEPIM/leniency/forced labour) + PGFN debt and fiscal regularity (Simples/MEI, CND hint) + IBAMA embargoes + court cases (DJEN, 12 months) + OFAC/UN/EU screening + economic group (companies sharing partners) + 0-100 risk score + per-section data quality. No contracts, BNDES or gazettes. Signed answer (Ed25519 attestation), verifiable at /v1/verify.

NameTypeReqDescription
cnpjstringyesBrazilian CNPJ, 14 characters, with or without punctuation (e.g. 00.000.000/0001-91).
NameTypeReqDescription
attestationobject–Ed25519 signature of this answer; verify at verify_url or with the public key at /.well-known/kyb-attestation.json.
cachedbooleanyes–
cnpjstringyesNormalized 14-character CNPJ.
companyobjectyes–
data_freshnessstringyes–
data_qualityarrayyesPer-section data age: fresh, aging, stale, unavailable or unknown.
economic_group–yesOther active companies sharing a partner, with their sanction/embargo flags (null = registry unavailable).
environmental_embargoes–yes–
federal_debt–yes–
fiscal_regularityobjectyes–
generated_atstringyes–
international_sanctions–yes–
receiptobject–Re-read this answer free for 10 minutes with br_replay.
riskobjectyes–
sanctions–yes–
sourcesarrayyesSource URL and fetch time of each fact.
summaryobjectyesShort summary in English and Portuguese.
warningsarrayyes–

No examples provided.

br_sanctions_screen ~160

Screen a Brazilian CNPJ, all branches of the same company (CNPJ root) and its corporate partners against the official CGU sanction lists: CEIS (debarred), CNEP (anti-corruption penalties), CEPIM (barred non-profits), leniency agreements, plus the Ministry of Labour forced-labour employer list. Each hit has type, body, dates, active flag and an evidence URL. Beyond a plain CEIS/CNEP check. Signed answer (Ed25519 attestation), verifiable at /v1/verify.

NameTypeReqDescription
cnpjstringyesBrazilian CNPJ, 14 characters, with or without punctuation (e.g. 00.000.000/0001-91).
NameTypeReqDescription
active_hitsnumberyes–
attestationobject–Ed25519 signature of this answer; verify at verify_url or with the public key at /.well-known/kyb-attestation.json.
cachedbooleanyes–
clearbooleanyesTrue when there is no ACTIVE sanction on the company, its branches or corporate partners.
cnpjstringyesNormalized 14-character CNPJ.
data_freshnessstringyes–
expired_hitsnumberyes–
generated_atstringyes–
hitsarrayyesEach hit: list, sanctioned_entity, sanction_type, dates, active, evidence_url.
receiptobject–Re-read this answer free for 10 minutes with br_replay.
screened_entitiesarrayyes–
sourcesarrayyesSource URL and fetch time of each fact.
summaryobjectyesShort summary in English and Portuguese.

No examples provided.

Install

How do I install the io.github.celfons/kyb-brasil MCP server?

io.github.celfons/kyb-brasil is a hosted endpoint at https://kyb-br-agents.marcelfons.workers.dev/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

remote · kyb-br-agents.marcelfons.workers.dev

# add to Claude Code
claude mcp add --transport http celfons-kyb-brasil 'https://kyb-br-agents.marcelfons.workers.dev/mcp'
Common questions

What is the io.github.celfons/kyb-brasil MCP server?

io.github.celfons/kyb-brasil is an MCP server listed in the public MCP registry as io.github.celfons/kyb-brasil. Brazilian KYB beyond registry checks: CGU sanctions, forced labour, PGFN, IBAMA, signed risk score. This page covers its hosted endpoint (https://kyb-br-agents.marcelfons.workers.dev/mcp).

Is the io.github.celfons/kyb-brasil MCP server safe to use?

io.github.celfons/kyb-brasil scores 69 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

What tools does the io.github.celfons/kyb-brasil MCP server expose?

io.github.celfons/kyb-brasil exposes 11 tools: br_about, br_company_check, br_company_search, br_company_count, br_replay, and 6 more. Their descriptions and schemas cost roughly 1,526 tokens of context every time the server is loaded.

Does the io.github.celfons/kyb-brasil MCP server require authentication?

No. We connected to io.github.celfons/kyb-brasil without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

Is the io.github.celfons/kyb-brasil MCP server still maintained?

io.github.celfons/kyb-brasil is still listed as active in the MCP registry. We last reached this channel on 18 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.