recon-tool 2.5.5

Domain intelligence CLI and MCP server — tech stack, email security, and signal intelligence from DNS.

recon

Passive domain intelligence from public sources. recon reads public DNS, certificate transparency, and unauthenticated Microsoft and Google identity discovery endpoints to compose typed observations around a domain's public technology and identity namespace. A domain is the query coordinate, not proof of one organization, owner, account, or deployed product.

It uses no credentials, no API keys, no paid feeds, and no active scanning. It is a local Python CLI, importable library, JSON producer, and stdio MCP server. It is not a hosted service, scheduler, vulnerability scanner, company research tool, or firmographic database.

Defensive use only. Use recon for legitimate posture review, IT architecture review, vendor diligence, and defensive hardening. See docs/legal.md for the intended-use policy.

Quick Start

Install with uv or pipx:

uv tool install recon-tool
# or
pipx install recon-tool

Python 3.11 through 3.14 is supported. The latest Python 3.14 patch is recommended for new installations and development; older supported versions retain the same product behavior and output contracts. Current measurements and version-specific decisions are in docs/performance.md.

If uv or pipx is already installed, the platform script can install or update recon:

Windows (PowerShell):

powershell -ExecutionPolicy ByPass -c "irm https://raw.githubusercontent.com/blisspixel/recon/main/scripts/install.ps1 | iex"

macOS or Linux:

curl -fsSL https://raw.githubusercontent.com/blisspixel/recon/main/scripts/install.sh | bash

Open a new terminal and run an offline verification of the installed command:

recon --version

Optionally test online connectivity to recon's public data sources:

recon doctor

Before the first lookup, note that recon makes DNS queries which recursive and authoritative DNS infrastructure may observe. Its only default request to a target-owned HTTP endpoint is the standards-defined MTA-STS policy fetch at https://mta-sts.<domain>/.well-known/mta-sts.txt. Google CSE and BIMI direct probes run only when --direct-probes is explicitly enabled.

Run the first lookup:

recon contoso.com

Example output shape:

Contoso Ltd
contoso.com

Provider     Microsoft 365 (MX delivery path) + Proofpoint gateway (MX delivery path)
Tenant       a1b2c3d4-e5f6-7890-abcd-ef1234567890
Auth         Federated
Confidence   High (4 sources)

Services
  Email       Microsoft 365, Proofpoint, DMARC, DKIM, SPF strict
  Identity    Okta, Entra ID
  Cloud       Cloudflare, AWS Route 53

Insights
  Federated identity observed; identity-vendor indicators: Okta
  Email security: observed controls: DMARC reject, DKIM, SPF strict, BIMI
  MX gateway observed: Proofpoint

Examples use Microsoft's fictional company names. Tenant IDs, services, and domains in examples are fabricated. No real company is depicted.

For detailed install, update, uninstall, and first-run workflows, read docs/getting-started.md.

What recon Is Good For

Need	Use recon for	Use something else when
Fast external stack context	Passive DNS, identity-endpoint, CT, SaaS, and posture indicators	You need authenticated tenant inventory or asset-management truth
Defensive review or vendor diligence	Hedged observations and evidence traces you can verify	You need vulnerability scanning, exploit checks, or host-level facts
Automation-friendly output	Stable JSON, batch mode, delta mode, and local MCP tools	You need dashboards, scheduling, or report generation built in

recon reports observations, not verdicts. A missing DMARC record is a missing record. A Microsoft 365 tenant indicator is an observed indicator. The operator decides what those facts mean in context.

Common Commands

recon contoso.com                              # default panel
recon https://www.contoso.com/path             # normalize URL to apex
recon mail.contoso.com                         # reduce sub-host to apex
recon mail.contoso.com --exact                 # keep that literal host
recon contoso.com --explain                    # reasoning and provenance
recon contoso.com --full                       # expanded evidence, domains, posture
recon contoso.com --json                       # structured lookup record
recon batch domains.txt --json                 # batch JSON array
recon batch domains.txt --ndjson               # one record per line
recon batch domains.txt --summary              # aggregate-only cohort summary
recon delta contoso.com                        # diff against cached snapshot
recon mcp install --client=cursor              # wire MCP into a client
recon mcp doctor                               # live MCP handshake check

Built-in posture profiles: fintech, healthcare, saas-b2b, high-value-target, public-sector, and higher-ed. Custom profiles live in ~/.recon/profiles/*.yaml.

Generated command and flag reference: docs/cli-surface.md.

How recon Works

recon reads:

• DNS records: MX, TXT, SPF, DMARC, DKIM, BIMI, CNAME, NS, SRV, and CAA.
• Certificate transparency: SAN names, issuers, issuance timing, and bounded related-domain hints.
• Identity discovery: unauthenticated Microsoft and Google endpoints.

Default collection includes bounded DNS queries through the configured recursive resolver, so authoritative DNS infrastructure may observe resulting resolver traffic. The only default target-owned HTTP or application request is the standards-based MTA-STS policy fetch at mta-sts.<domain>. Google CSE and BIMI VMC direct probes are opt-in behind --direct-probes.

The engine then maps observables to fingerprint slugs, derived signals, typed topology, provenance paths, per-slug evidence strength, and model-relative Bayesian diagnostics. Sparse public evidence stays sparse: the result lowers confidence or remains unresolved instead of inventing a clean answer. A source failure remains unavailable rather than becoming a negative observation. The Bayesian uncertainty band is evidence-responsive, not a demonstrated credible or confidence interval.

The reviewed built-in fingerprint source remains split YAML. Release wheels load one deterministic generated JSON catalog, while custom and session-scoped fingerprints still pass through the runtime validator. This keeps contributor review readable and removes repeated YAML parsing from cold CLI startup without changing catalog order, matching, or public output.

Long-form explanation: docs/how-it-works.md. Formal model and robustness research program: docs/correlation.md.

JSON and Automation

recon <domain> --json emits a stable single-domain lookup object. Batch and delta modes emit different shapes, so route by mode or by record_type. recon batch --summary --json preserves the separate aggregate-only cohort_summary 2.1 contract. New consumers can select --summary-schema 2.2 for raw-evidence-bound DMARC rates, corrected missingness, and explicit metric kinds. The standalone reducer uses --schema-version 2.2 for the corresponding atemporal compatibility view.

recon contoso.com --json
recon batch domains.txt --json
recon batch domains.txt --ndjson
recon delta contoso.com --json

Read these before building an integration:

• docs/schema.md: stable JSON contract.
• docs/recon-schema.json: machine-readable schema.
• docs/automation-examples.md: parser examples.
• docs/operational-contract.md: timeouts, bounds, exit codes, cache, and partial-result semantics.

docs/surface-inventory.json, docs/cli-surface.md, and recon://surface-inventory are generated discovery context and drift guards, not stable runtime API contracts. ADR-0007 records the promotion gate for any future stable subset.

MCP Server

The default install includes a local stdio MCP server for MCP-compatible tools. Start with manual approvals and an empty autoApprove list. Treat connected agents as untrusted input.

recon mcp install --client=claude-desktop
recon mcp install --client=cursor --dry-run
recon mcp doctor

The installer writes the right per-client config shape and preserves sibling MCP servers. Full setup, tool list, read-only versus stateful guidance, and troubleshooting live in docs/mcp.md. Per-client scaffolds live in agents/.

Limitations

The public channel has a ceiling:

• Internal-only workloads are invisible.
• SaaS products without DNS verification records may not appear.
• Email gateways can hide the downstream mailbox provider.
• CT logs can be stale, partial, rate-limited, or absent.
• Fingerprints are rule-based indicators, not proof of active use.

Read docs/limitations.md before using recon output for a high-stakes decision. Read docs/data-handling-policy.md before committing any validation artifact.

Documentation

• docs/getting-started.md: install, update, uninstall, and first commands.
• docs/how-it-works.md: readable model overview.
• docs/README.md: complete docs index.
• docs/roadmap.md: current plan, invariants, and scope boundaries.
• docs/external-writeup-plan.md: active maintainer plan for external write-up readiness.
• docs/submission-freeze-checklist.md: final paper and artifact freeze gate before any external submission package.
• docs/c3-ct-validation-plan.md: closed certificate-transparency validation plan.
• CHANGELOG.md: shipped changes.

Roadmap Focus

recon has a stable baseline, but product quality work remains. The top three priorities are:

1. Make every default claim traceable to evidence and remove product-use, cloud-type, or security-maturity conclusions that public metadata cannot support.
2. Establish an aggregate-safe quality baseline for claim precision, abstention, provenance, catalog coverage, degradation, latency, CT value, and agent context cost before expanding inference or graph machinery.
3. Keep the exact MCP v1.28.1 and v2.0.0b1 compatibility matrix green, then repeat the full gate against the final 2026-07-28 specification and stable v2 SDK before changing the production dependency.

The dependency order, acceptance evidence, stop rules, and current code-graph summary live in docs/roadmap.md. The implementation plan is docs/engineering-refinement-plan.md, and the current step-back review is docs/strategic-gap-audit.md. Research publication, OpenSSF process, outside replication, and archive work remain separate maintainer tracks so they do not displace product truthfulness or measured utility.

The latest local public proof for the separate publication track is validation/2026-06-30-submission-freeze-local-proof.md. Its public-label decision keeps public lists as robustness checks rather than population rates, and its M365 tenancy decision keeps that evidence as corroboration rather than independent calibration.

Development

uv sync
pre-commit install
uv run python scripts/release_readiness.py --allow-dirty
uv run python scripts/check.py

python scripts/check.py is the local CI mirror. It runs lint, type checks, coverage-gated tests, generated-artifact checks, validation hygiene, and ratchets. Its full-suite stage uses at most four file-grouped test workers while preserving combined branch coverage. Focused pytest commands stay serial by default. Do not push on --fast alone.

Project hygiene: keep examples fictional or synthetic, keep validation artifacts aggregate-only, run scripts/check.py, and avoid dead code or placeholders. Contributor details: CONTRIBUTING.md.

License

Apache 2.0. Free to use, build on, fork, and share. See LICENSE for the full terms.