Dechonet MCP

Brand Impersonation Exposure

impersonation_exposure

Read-onlyIdempotent

Assess a domain's exposure to brand impersonation and phishing by checking resolving lookalike domains, exposed subdomains in CT logs, and wildcard certificates; returns an A+ to F grade.

Instructions

Assess how exposed a domain is to brand impersonation and phishing, PASSIVELY: live typosquat/lookalike domains (homoglyph, omission, transposition, TLD swap) that actually resolve, operational subdomains (dev/staging/admin) exposed in CT logs, and whether a wildcard certificate exists — returning an A+ (low exposure) to F (high exposure) grade. Framing: a registered lookalike domain is not proof of impersonation — it may be a legitimate third party or the owner's own — so report it as exposure to verify, not as an accusation against that domain. Fully passive: public DNS delegation checks plus public CT-log queries, sending nothing to the target or the lookalike domains, so it is safe and lawful to run. Use lookalike_domains or subdomain_discovery for the raw per-tool detail. Read-only; requires no API key; rate-limited. Returns a text report: grade, counts, per-category findings, and a shareable report link.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`domain`	Yes	Registrable domain to assess for impersonation exposure (e.g., 'example.com'). Scheme and path are stripped.

Output Schema

TableJSON Schema

Name	Required	Description
`grade`	Yes	Exposure grade A+ (low exposure) to F (high exposure)
`score`	Yes	0-100, higher = less exposed
`receipts`	No	Signed observation receipts behind this result, one per lookup: when, from where and under which rules version DechoNet observed it. Each url shows the record and checks its Ed25519 signature.
`wildcard`	No	Whether a wildcard certificate exists
`reportUrl`	Yes	Human-facing interactive report on dechonet.com
`typosquatCount`	Yes	Live third-party lookalike/typosquat domains (variants on the domain's own nameservers/IP are excluded)
`riskySubdomainCount`	Yes	Exposed operational subdomains found

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv1.5.14Oct 15, 2026

addedOutput schema / properties / receipts

Added value: +{
+  "description": "Signed observation receipts behind this result, one per lookup: when, from where and under which rules version DechoNet observed it. Each url shows the record and checks its Ed25519 signature.",
+  "items": {
+    "additionalProperties": false,
+    "properties": {
+      "id": {
+        "type": "string"
+      },
+      "tool": {
+        "type": "string"
+      },
+      "url": {
+        "type": "string"
+      }
+    },
+    "required": [
+      "tool",
+      "id",
+      "url"
+    ],
+    "type": "object"
+  },
+  "type": "array"
+}

Addedv1.2.2Sep 22, 2026

TDQS

A4.6/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnly/openWorld/idempotent/non-destructive, but the description adds substantial context beyond that: the operation is fully passive, sends nothing to the target or lookalikes, uses public DNS delegation and CT-log queries, is rate-limited, and returns a shareable report link. It also flags an important interpretive caveat (a registered lookalike is exposure to verify, not proof of impersonation), which is genuine behavioral guidance.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The paragraph is long but well front-loaded with purpose, then method, grade, caveat, passivity, alternatives, and constraints. Nearly every sentence earns its place, though the passive/no-data-sent point is restated and could be tightened slightly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given an output schema exists, the description need not explain returns, yet it usefully summarizes the report contents (grade, counts, per-category findings, report link). Together with the method, constraints, and caveat, an agent has everything needed to call and interpret this tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% for the single 'domain' parameter, and the schema already documents that scheme/path are stripped and gives an example. The description adds no parameter-level syntax beyond what the schema provides, so the baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Assess how exposed a domain is to brand impersonation and phishing') and enumerates the exact checks performed (typosquat/lookalike domains, CT-log subdomains, wildcard cert). It explicitly distinguishes itself from lookalike_domains and subdomain_discovery, so an agent can separate it from siblings without opening another schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Names the alternative tools and the condition that selects them ('Use lookalike_domains or subdomain_discovery for the raw per-tool detail'), routing the agent to this tool for the aggregated grade. It also states prerequisites (read-only, no API key, rate-limited) and the passive operating constraint.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.