An integration guide for Resend, an email-sending service, and its official tools. It covers the service’s API, which lets software send and manage email through code.

It helps send or schedule individual and batch emails, use templates, verify domains and DNS, manage contacts and mailing lists, handle inbound email and attachments, and work with webhooks.

It helps developers connect email features without guessing how sending, domains, authentication, or incoming messages work.

resend-api — Skill for Claude Code and Codex by tristanmanchester

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 tristanmanchester/agent-skills --skill resend-api

Clone the repo

git clone --depth 1 https://github.com/tristanmanchester/agent-skills

Made for: Claude Code, Codex.

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/tristanmanchester/agent-skills/resend-api/github.svg)](https://agentmods.dev/skills/tristanmanchester/agent-skills/resend-api)

Your own site

<a href="https://agentmods.dev/skills/tristanmanchester/agent-skills/resend-api"><img src="https://agentmods.dev/badge/skills/tristanmanchester/agent-skills/resend-api/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/tristanmanchester/agent-skills/resend-api"><img src="https://agentmods.dev/badge/skills/tristanmanchester/agent-skills/resend-api.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 61 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,148 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.

Origin unknown 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.

Model	Per session	Once invoked
Fable 5.1	$0.00061	$0.01148
Opus 5.5	$0.00024	$0.00459
Sonnet 5.5	$0.00012	$0.00230
Haiku 4.5	$0.00006	$0.00115

Measured 1mo ago against content hash 9de532183a8a, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

resend-api 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 1mo 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.

resend-api/SKILL.md · 104 lines

The source is not reproduced here

No licence file

Read it on GitHub

Files

What ships with it

4 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.

1mo ago Changed · -58 lines · -60 tokens per session 9de532183a8a
2mo ago First seen · 162 lines · 121 tokens per session scan A 59b2ded119c9

Subscribe to this mod's changes

resend-api is a skill published in the GitHub repository tristanmanchester/agent-skills (4 stars, last pushed 1mo ago), with no licence file. It adds 61 tokens to every session and 1,148 once invoked, about $0.0002 per session on Opus 5.5. 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 2026-08-31.

Backend and APIs

resend-api next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
resend-apitristanmanchester/agent-skills	Skill	4	1mo ago	none	A	61	Claude Code, Codex
mem0-oss-to-platformmem0ai/mem0	Skill	69k	yesterday	Apache-2.0	A	217	Claude Code, Codex
azure-mgmt-botservice-dotnetmicrosoft/skills	Skill	3.2k	yesterday	MIT	A	78	Claude Code
fastapi-router-pymicrosoft/skills	Skill	3.2k	yesterday	MIT	A	46	Claude Code
dev-runtimelangwatch/langwatch	Skill	5.0k	today	Apache-2.0	A	172	Claude Code
api-designericrisco/rsc-harness	Skill	529	3d ago	MIT	A	105	Claude Code, Codex
migrate-segw-to-raparc-mcp/arc-1	Skill	253	today	MIT	A	106	Claude Code