osint-mcp-server

dns_spf_chain

Recursively trace SPF include chains to reveal all domains, IP ranges, and services like Google Workspace, while checking RFC 7208 lookup limit compliance.

Instructions

Recursively resolve SPF include chain. Shows all included domains, IP ranges, detected services (Google Workspace, Microsoft 365, SendGrid, etc.), and RFC 7208 lookup limit compliance.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "domain": "<domain>"
    },
    "name": "dns_spf_chain"
  }
}

Input Schema

Name	Required	Description	Default
`domain`	Yes	Domain to trace SPF chain for
`max_depth`	No	Maximum recursion depth (default: 10)

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.2.0Mar 17, 2026

TDQS

A4.1/5.0

Behavior4/5

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

Without annotations, the description effectively discloses recursive behavior, output contents, and compliance checking. However, it does not mention potential limitations like DNS rate limits or timeouts, which would enhance transparency.

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

Conciseness5/5

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

The description is a single, well-structured sentence with no extraneous words. Every clause adds value: 'Recursively resolve', 'SPF include chain', and the list of outputs.

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 the tool's complexity (SPF chain resolution with recursion and service detection) and lack of output schema, the description sufficiently covers what the tool does and what results to expect, leaving little ambiguity.

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 coverage is 100%, so the parameters are already documented. The description adds context about recursion and max_depth but does not significantly augment the parameter meanings beyond what the schema provides.

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?

The description clearly states the tool's action: recursively resolve SPF include chains. It specifies the outputs: included domains, IP ranges, detected services, and RFC compliance, which differentiates from sibling tools like dns_lookup or dns_email_security.

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

Usage Guidelines3/5

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

The description implies usage for SPF chain analysis but provides no explicit guidance on when to use it versus alternatives like dns_lookup or dns_email_security. No exclusions or prerequisites are mentioned.

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