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Sigil

Sigil v1.0.5

Honest brand critiques

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Competitor profile

Developer declarations; not independently tested. Listing last checked Nov 4, 2026. Package observed Nov 3, 2026.

Declared capabilities

  • Critiques a company's brand from its website
  • Reads one pitch deck, memo or brief by link
  • Scores clarity, distinctiveness, credibility, coherence, voice and craft

Cost & access

The plugin provides brand critiques. It does not offer digital purchases or checkout.

Declared limitations

  • Refuse a private network website before starting a brand review.
  • Ask for the public website. The server rejects a missing website argument.
  • Report that the brand review does not exist; do not expose another report.

Onboarding example

Critique the brand of autoprintstudio.com

View onboarding source →

View package source →

Description

From the marketplace listing

Sigil critiques a company’s brand from its public website and an optional public document. The brand review covers positioning, visual identity, voice, a brand score, and the changes to make first. The plugin returns the critique and a link to the full brand review. It does not design logos, generate brand briefs, or access private company systems.

Language: English · Automatically detected from descriptions.

ChatGPT marketplace listing ↗Website ↗Privacy policy ↗Terms ↗Support ↗

What changed

Files & skills

File archives

Plugin package7 files · 7.31 KBBrowse files →
Skill instructions
sigil893 Bytes

View saved version →

---
name: sigil
description: Critique a company’s brand from its public website and an optional public product document through Sigil’s MCP tools.
---

# Sigil

Use Sigil when the user wants feedback on an existing brand, positioning, visual identity, voice or website. Ask for a public website if the user has not supplied one. If they provide a public document URL, pass it as document_url. Call start_read once, then check_read with its ID until the result is ready. Summarize the requested part of the actual report and provide its returned link. Reuse an existing review ID for follow-up questions; do not start duplicate work.

Do not fabricate a score or report. Handle server refusals in plain language. Sigil’s tools cannot generate logos, complete brand briefs, access private network websites or charge users. Do not advertise digital purchases or paid offers in this plugin.

Release notes

Update public links to sigilbrandstudio.com and use brand review terminology. Keep Sigil as the listing and author name, with the registered public MCP endpoint unchanged.

Declared in the saved package. Remote tools may change independently.

Package details

Publisher declarations from the archived package. These are separate from our research and the live service's terms.

Package author
Sigil
Getting started skill
./skills/sigil/SKILL.md
Commerce declaration
Does not support commerceThis does not establish whether access is free or paid.
Review scenarios
5 positive · 3 negativeScenario counts, not test results.

Declared capabilities

  • Critiques a company's brand from its website
  • Reads one pitch deck, memo or brief by link
  • Scores clarity, distinctiveness, credibility, coherence, voice and craft
  • Suggests a one-line brand idea and the first changes to make

Package observed Nov 3, 2026.

plugin.json
Technical details
First seen
Oct 24, 2026 · 12:40 UTC
Last seen
Nov 4, 2026 · 06:00 UTC
Collection status
Collected

plugin_asdk_app_6ac07c086e348191bd3a0f664f179b59

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