twilio-sendgrid-deliverability-advisor

twilio-sendgrid-deliverability-advisor is a skill for Claude Code, Codex from twilio/ai. It costs 156 tokens per session (3,570 once invoked), scanned A, original, MIT.

A diagnostic guide for email deliverability, the ability of sent messages to reach recipients' inboxes. It covers spam placement, bounces, blocks, sender reputation, and SendGrid-related authentication.

In plain words
What is it for?
Use it to investigate SPF, DKIM, DMARC, BIMI, IP warm-up, list hygiene, spam complaints, blacklists, and other inbox-placement issues.
Why use it?
It helps identify why messages are filtered, rejected, delayed, or bouncing instead of treating every delivery problem as a sending-code bug.

Skill for Claude CodeCodex ✓ vendor

Written for Claude Code and Codex: shipped in a Claude Code plugin, but also agents/openai.yaml present.

Part of the ai plugin — 57 skills shipped together

Good fit Use it to investigate SPF, DKIM, DMARC, BIMI, IP warm-up, list hygiene, spam complaints, blacklists, and other inbox-placement issues.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/twilio/ai/twilio-sendgrid-deliverability-advisor
View source ↗ twilio/ai
About the project

Twilio for AI provides coding agents with skills and an MCP server for using Twilio services and documentation. The MCP server searches Twilio documentation and API specifications and retrieves full schemas for selected operations, while the skills supply procedural guidance to agents. Its catalogue add-ons are intended for Claude Code, Cursor, Codex, and other tools that support the Agent Skills standard.

twilio/ai · 32 stars · on GitHub

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add twilio/ai --skill twilio-sendgrid-deliverability-advisor
Clone the repo
git clone --depth 1 https://github.com/twilio/ai

Made for: Claude Code, Codex.

Or install ai, the plugin that ships this one along with the rest of its 57 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for twilio-sendgrid-deliverability-advisor

README.md
[![agentmods](https://agentmods.dev/badge/skills/twilio/ai/twilio-sendgrid-deliverability-advisor/github.svg)](https://agentmods.dev/skills/twilio/ai/twilio-sendgrid-deliverability-advisor)
Your own site
<a href="https://agentmods.dev/skills/twilio/ai/twilio-sendgrid-deliverability-advisor"><img src="https://agentmods.dev/badge/skills/twilio/ai/twilio-sendgrid-deliverability-advisor/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for twilio-sendgrid-deliverability-advisor

Your own site · 80×15
<a href="https://agentmods.dev/skills/twilio/ai/twilio-sendgrid-deliverability-advisor"><img src="https://agentmods.dev/badge/skills/twilio/ai/twilio-sendgrid-deliverability-advisor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 156 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,570 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00156 $0.03570
Opus 5 $0.00078 $0.01785
Sonnet 5 $0.00031 $0.00714
Haiku 4.5 $0.00016 $0.00357

Measured 10d ago against content hash f008f75a4705, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

twilio-sendgrid-deliverability-advisor scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/sendgrid/twilio-sendgrid-deliverability-advisor/SKILL.md · 261 lines

How it starts

The opening of the file, as written. The whole thing — 261 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Role

You are an Email Deliverability Advisor. When a developer describes emails going to spam, bouncing, getting blocked, or asks how to improve inbox placement or sender reputation, use this framework to diagnose and recommend fixes.

When This Skill Activates

Trigger on any of these signals:

  • "Emails going to spam," "landing in junk," "not reaching inbox"
  • "Blocked," "rejected," "deferred," "blacklisted," "denylisted"
  • "Bounce rate too high," "spam complaints," "reputation score"
  • "IP warmup," "dedicated IP," "shared IP"
  • "SPF," "DKIM," "DMARC," "BIMI," "domain authentication"
  • "SEQ score," "engagement quality," "sender score"
  • "List hygiene," "spam traps," "invalid addresses"
  • "How do I improve deliverability?"

Do NOT trigger for: general email sending implementation, template questions, webhook setup, suppression list management unrelated to deliverability. Redirect to twilio-sendgrid-email-send (SendGrid) for sending questions, twilio-sendgrid-suppressions for suppression management, twilio-email-deliverability-advisor for Twilio Email deliverability.


Step 0: Identify Platform

Check for platform signals before proceeding:

Signal Platform Action
API key starts with SG. SendGrid Proceed
Mentions app.sendgrid.com SendGrid Proceed
Mentions comms.twilio.com, Account SID, or Auth Token Twilio Email Redirect
No signal Unknown Ask

If Twilio Email: Stop. Respond: "For Twilio Email deliverability, use the twilio-email-deliverability-advisor skill — it's scoped to that platform."

If unclear: Ask exactly this before proceeding:

"Are you using SendGrid (API key starting with SG., dashboard at app.sendgrid.com) or Twilio Email (Twilio Account SID / Auth Token)?"


Step 1: Detect the Problem Type

Acute problem (emails suddenly blocked, bounce rate spiked, on a denylist): → TRIAGE MODE. Something changed — diagnose before recommending.

Gradual degradation (deliverability declining over weeks, open rates dropping): → AUDIT MODE. Systematic review of authentication, list health, and sending patterns.

Read the full file on GitHub · 261 lines

Files

What ships with it

3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 10d ago First seen · 261 lines · 156 tokens per session scan A f008f75a4705

Subscribe to this mod's changes

twilio-sendgrid-deliverability-advisor is a skill published in the GitHub repository twilio/ai (32 stars, last pushed 26d ago), licensed MIT. It adds 156 tokens to every session and 3,570 once invoked, about $0.0008 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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