domain-security-mcp-server

TLS-RPT Check

tls_rpt_check

Read-onlyIdempotent

Check a domain's TLS-RPT record to see if it publishes reporting for TLS delivery failures. Returns record details and findings in Markdown or JSON.

Instructions

Check a domain's TLS-RPT record (_smtp._tls. TXT). TLS-RPT lets you receive reports about TLS delivery failures to your domain.

Args:

domain (string): the domain to check.
response_format ('markdown' | 'json'): output format (default 'markdown').

Returns: { found, record, findings[] }.

Example: "Does microsoft.com publish TLS-RPT?" -> tls_rpt_check(domain="microsoft.com").

Input Schema

TableJSON Schema

Name	Required	Description	Default
`domain`	Yes	Domain to check, e.g. 'example.com'.
`response_format`	No	Output format: 'markdown' for a human-readable summary (default) or 'json' for the full structured payload.	markdown

Output Schema

TableJSON Schema

Name	Required	Description	Default
`found`	Yes
`domain`	Yes
`record`	No
`findings`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed4 schema fields changedv1.2.1Sep 14, 2026

changedInput schema / $schema

Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"

removedInput schema / additionalProperties
```
Removed value: -false
```
addedInput schema / properties / domain / maxLength
```
Added value: +253
```

changedOutput schema / $schema

Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"

First observedv1.0.0Jun 8, 2026

TDQS

A3.9/5.0

Behavior3/5

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

Annotations already cover readOnlyHint, openWorldHint, idempotentHint, and destructiveHint. The description adds the return-shape note and a usage example, but does not add behavioral details such as DNS lookups, timeout behavior, or error conditions. The description is consistent with annotations and adds some practical value.

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 description is well-organized and front-loaded with purpose, followed by argument and return details. The Args/Return sections add some redundancy with the schema, but they are brief and the example is useful.

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

Completeness4/5

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

For a low-complexity read-only lookup tool with full schema coverage and annotations, the description is largely complete. It could be slightly stronger with a note about when to use this versus the broader email_auth_audit, but nothing important is missing for directly calling the 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 coverage is 100%, and the description mostly restates the schema: domain and response_format semantics are already detailed in the schema. The example invocation does add a tiny bit of practical guidance, but not enough to move above baseline.

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 states a specific verb and resource: 'Check a domain's TLS-RPT record (_smtp._tls.<domain> TXT)'. It identifies the exact record type and purpose, making it easily distinguishable from sibling tools like dmarc_check, spf_check, and dkim_check.

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?

The description gives clear context: TLS-RPT is for receiving reports about TLS delivery failures, so an agent can infer when this tool is relevant. It does not explicitly name alternatives or exclusions, but the context is clear enough for a single-purpose DNS check.

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