[FEATURE] DNS Doctor tools: domain scan, DMARC upgrade, propagation check

Feature Area

Integration with external tools

Is your feature request related to a an existing bug? Please link it here.

NA

Describe the solution you'd like

Add tools over the hosted DNS Doctor API to lib/crewai-tools, so a crew can check and fix a domain's DNS and email authentication without a model guessing at records:

• DnsDoctorScanTool: the full report for a domain (SPF, DKIM, DMARC, MX, DNS health, blacklists, domain and TLS expiry) with deterministic per-check verdicts and copy-paste fix records produced by a validating engine.
• DnsDoctorDmarcUpgradeTool: the next safe DMARC record for a domain, alignment-gated, with the rationale (the record can be null; then the rationale is the answer).
• DnsDoctorPropagationTool: whether a DNS change has propagated, read from six locations on four continents.

No API key is needed; an optional DNSDOCTOR_API_TOKEN raises the rate limit. The tools use the existing requests dependency, relay responses verbatim as JSON text, and return transport failures (rate limit, 5xx, network) as text that says they are not a verdict about the domain, so an agent never reads an outage as a finding.

Describe alternatives you've considered

Wrapping the API in a custom tool inside each crew. That works, but every crew re-implements the same failure handling and loses the safety wording (verbatim records, transient is not a verdict) that keeps agents from inventing DNS records.

Additional context

Implementation is ready: tool folder with README, pydantic args_schema with an enum for record types, env_vars declared, exports in both __init__ files, the three generated tool.specs.json entries, and network-mocked tests (uv run --package crewai-tools pytest lib/crewai-tools/tests/tools/dns_doctor_tool_test.py, 6 passed; pre-commit clean). Authored with an AI coding assistant working from the contributing guide; please apply the llm-generated label if the reporter cannot.

Willingness to Contribute

Yes, I'd be happy to submit a pull request

Start in lib/crewai-tools and run the named network-mocked test at lib/crewai-tools/tests/tools/dns_doctor_tool_test.py to understand the expected behavior. Done means the three DNS Doctor tools, README, schemas, environment declaration, exports, tool.specs.json entries, and transport-failure wording are covered by the tests and pre-commit remains clean.