What is atproto-attestation?

A development guide for adding attestations to AT Protocol records according to the badge.blue specification. An attestation is a signed or linked proof that a particular record is associated with a claim.

Use it when implementing, debugging, or reasoning about inline or remote attestations in Rust, TypeScript, or Go.

It provides the exact rules needed to create or check these proofs, including the record identifier and signature formats. This reduces mistakes when implementing the same behavior in different programming languages.

atproto-attestation — Skill for Claude Code by ngerakines

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 ngerakines/atproto-skills --skill atproto-attestation

Clone the repo

git clone --depth 1 https://github.com/ngerakines/atproto-skills

Made for: Claude Code.

Or install atproto-skills, the plugin that ships this one along with the rest of its 7 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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/ngerakines/atproto-skills/atproto-attestation/github.svg)](https://agentmods.dev/skills/ngerakines/atproto-skills/atproto-attestation)

Your own site

<a href="https://agentmods.dev/skills/ngerakines/atproto-skills/atproto-attestation"><img src="https://agentmods.dev/badge/skills/ngerakines/atproto-skills/atproto-attestation/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/ngerakines/atproto-skills/atproto-attestation"><img src="https://agentmods.dev/badge/skills/ngerakines/atproto-skills/atproto-attestation.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 516 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 3,787 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 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.

Model	Per session	Once invoked
Fable 5.1	$0.00516	$0.03787
Opus 5.5	$0.00206	$0.01515
Sonnet 5.5	$0.00103	$0.00757
Haiku 4.5	$0.00052	$0.00379

Measured 2mo ago against content hash ddb213f87afd, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

atproto-attestation 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 2mo 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/atproto-attestation/SKILL.md · 183 lines

How it starts

The opening of the file, as written. The whole thing — 183 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AT Protocol record attestations (badge.blue)

CID-first record attestations as specified at https://badge.blue/ and implemented in the atproto-attestation Rust crate. This skill routes to per-language guides for Rust, TypeScript, and Go, sitting on top of a language-neutral spec in shared/.

Defaults

An attestation binds a cryptographic or content-addressed claim to a specific record in a specific repository:

Content CID: CIDv1, codec 0x71 (dag-cbor), hash 0x12 (SHA-256), 32-byte digest, 36-byte binary form. Computed over a canonical merge of record (without signatures) + $sig metadata (without cid/signature, with repository inserted).
Inline attestation: the 36-byte CID bytes are ECDSA-signed (P-256 or K-256), normalized to low-S, base64-encoded (standard alphabet with padding), and embedded in record.signatures[] alongside the metadata.
Remote attestation: the content CID is written into a separate proof record in the attestor's repo; the subject record's signatures[] carries a com.atproto.repo.strongRef pointing at the proof record.

Full normative rules: shared/spec.md. Step-by-step CID procedure: shared/cid-computation.md. Inline flow: shared/inline-attestation.md. Remote flow: shared/remote-attestation.md. Signature normalization: shared/signature-normalization.md. Fixtures: shared/test-vectors.md. Cross-language differences: shared/divergence-matrix.md.

Language detection

Before generating or reviewing any attestation code, determine the target language from project files:

Cargo.toml, *.rs, any mention of atproto-attestation / atproto-identity / k256 / p256 → Rust — read from rust/. The reference crate lives here.
package.json, tsconfig.json, *.ts, *.tsx, imports of @noble/curves / @ipld/dag-cbor / multiformats → TypeScript — read from typescript/.
go.mod, *.go, imports of github.com/ipfs/go-cid / github.com/ipld/go-ipld-prime / github.com/decred/dcrd/dcrec → Go — read from go/.

Read the full file on GitHub · 183 lines

Files

What ships with it

19 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.

2mo ago First seen · 183 lines · 516 tokens per session scan A ddb213f87afd

Subscribe to this mod's changes

atproto-attestation is a skill published in the GitHub repository ngerakines/atproto-skills (53 stars, last pushed 6mo ago), licensed MIT. It adds 516 tokens to every session and 3,787 once invoked, about $0.0021 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 2026-08-30.

Security agentskills atproto atprotocol

atproto-attestation next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
atproto-attestationngerakines/atproto-skills	Skill	53	6mo ago	MIT	A	516	Claude Code
ops-demoSnowflake-Labs/cocoplus	Skill	727	2d ago	MIT	A	46	Claude Code
diarySnowflake-Labs/cocoplus	Skill	727	2d ago	MIT	A	12	Claude Code, Codex
pulse-configureSnowflake-Labs/cocoplus	Skill	727	2d ago	MIT	A	12	Claude Code, Codex
stall-resetSnowflake-Labs/cocoplus	Skill	727	2d ago	MIT	A	14	Claude Code, Codex
code-reviewmagnus919/agent-skills	Skill	166	2d ago	MIT	A	196	Claude Code, Codex
basic-skilldarkrishabh/agent-skills-eval	Skill	811	2d ago	MIT	A	17	Claude Code, Codex