Dechonet MCP

Lookalike Domain Check

lookalike_domains

Read-onlyIdempotent

Generate typosquat and homoglyph variants of a domain, then check which are registered to assess brand-impersonation and phishing exposure. Verify each hit with WHOIS.

Instructions

Generate the typosquat/lookalike variants of a domain that phishers actually register — homoglyph swaps (l→1, o→0, rn→m), TLD swaps (.com→.co), character omissions, transpositions, repetitions, hyphenations — and check which of them are currently registered (live NS delegation via DoH). Use this to assess brand-impersonation and phishing exposure for a domain the user is responsible for. A registered variant is NOT proof of abuse (it may be an unrelated legitimate site) — follow up with whois_lookup on each hit for its owner and registration date. Read-only; requires no API key; rate-limited. Returns generated/checked counts and the registered variants with the technique that produced each.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`domain`	Yes	Domain to protect (e.g., 'example.com'), without scheme or path. Variants of its label and TLD are generated and checked.

Output Schema

TableJSON Schema

Name	Required	Description
`kpis`	No	Key metrics as label/value pairs
`grade`	No	Letter grade (A+ to F) when the tool grades the target
`score`	No	0-100 score when the tool scores the target
`issues`	No	Detected problems, severity-rated
`status`	Yes	Overall verdict, e.g. 'good' \| 'warning' \| 'bad' \| 'info' \| 'unknown'
`actions`	No	Recommended next actions, most important first
`summary`	No	One-paragraph interpretation of the result
`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.
`reportUrl`	Yes	Human-facing interactive report for this exact lookup on dechonet.com
`observation`	No	How much was actually observed and when. A partial observation means some checks did not answer: missing parts are not verified, never clean.

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedv1.5.14Oct 15, 2026

addedOutput schema / properties / observation

Added value: +{
+  "additionalProperties": false,
+  "description": "How much was actually observed and when. A partial observation means some checks did not answer: missing parts are not verified, never clean.",
+  "properties": {
+    "ageMinutes": {
+      "type": [
+        "number",
+        "null"
+      ]
+    },
+    "cached": {
+      "type": "boolean"
+    },
+    "observedAt": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "state": {
+      "enum": [
+        "complete",
+        "partial",
+        "unknown"
+      ],
+      "type": "string"
+    }
+  },
+  "required": [
+    "state",
+    "observedAt",
+    "cached",
+    "ageMinutes"
+  ],
+  "type": "object"
+}

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"
+}

Addedv1.1.0Sep 8, 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, and the description adds what they cannot: no API key required, rate-limited, detection method (live NS delegation via DoH), and an important interpretation caveat that a registered variant is not proof of abuse. That result-semantics disclosure materially changes how an agent should act on output.

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?

One dense paragraph, front-loaded with the verb and the technique list, with no filler sentences. It is longer than strictly necessary and the technique enumeration stacks heavily, but every sentence carries operational information (caveat, follow-up, constraints, return shape).

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?

Despite an output schema already existing, the description summarizes return values (generated/checked counts plus registered variants tagged with the producing technique), and it covers constraints, interpretation limits, and next steps. Nothing an agent needs to select or invoke this tool correctly is missing.

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

Parameters4/5

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

With a single parameter at 100% schema coverage, the schema already documents format and exclusions (no scheme/path). The description adds marginal value by stating that both the label and the TLD are used to generate and check variants, which clarifies scope beyond the parameter's own text.

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+resource pair — generating typosquat/lookalike variants and checking which are registered via DoH — and enumerates the exact technique families (homoglyph, TLD swap, omission, transposition, repetition, hyphenation), so an agent can distinguish it from siblings like dns_lookup or whois_lookup without opening schemas.

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

Usage Guidelines4/5

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

Explicitly frames the use case (brand-impersonation/phishing exposure for a domain the user is responsible for) and routes the follow-up step to whois_lookup on each hit, which is concrete guidance. It stops short of naming when NOT to use it versus siblings such as impersonation_exposure, so it is clear context without full alternative coverage.

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