substrate-seeder

substrate-seeder is an agent for coding agents from nestharus/agent-implementation-skill. It costs 28 tokens per session (740 once invoked), scanned A, original, MIT.

A scaffolding agent that creates minimal shared files from an approved seed plan. These files define placeholder interfaces for sections to integrate with later.

In plain words
What is it for?
Use it to create stub anchor files, document their purpose, define minimal types or functions, and emit updates to related-file references.
Why use it?
It gives multiple implementation areas a common starting contract without attempting to build the full features.

Agent

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.

agentmods
npx agentmods add agents/nestharus/agent-implementation-skill/substrate-seeder
Clone the repo
git clone --depth 1 https://github.com/nestharus/agent-implementation-skill

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 substrate-seeder

README.md
[![agentmods](https://agentmods.dev/badge/agents/nestharus/agent-implementation-skill/substrate-seeder.svg)](https://agentmods.dev/agents/nestharus/agent-implementation-skill/substrate-seeder)
Your own site
<a href="https://agentmods.dev/agents/nestharus/agent-implementation-skill/substrate-seeder"><img src="https://agentmods.dev/badge/agents/nestharus/agent-implementation-skill/substrate-seeder.svg" alt="Measured on agentmods" height="20"></a>
Per session 28 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 740 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00028 $0.00740
Opus 5 $0.00014 $0.00370
Sonnet 5 $0.00006 $0.00148
Haiku 4.5 $0.00003 $0.00074

Measured yesterday against content hash 533143a5ab60, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

substrate-seeder 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 yesterday.

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.

src/scan/agents/substrate-seeder.md · 120 lines

How it starts

The opening of the file, as written. The whole thing — 120 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Substrate Seeder

You create the minimal anchor files described in a seed plan and wire them into the pipeline so sections can integrate against them.

Method of Thinking

Think about creating the minimum viable anchor, not implementing features. Each anchor file is a stub — it defines the interface or convention that sections will integrate against. It is NOT a full implementation.

Accuracy First — Zero Tolerance for Fabrication

Read the seed plan and substrate document completely. Every anchor must match the seed plan exactly. Do not add anchors not in the plan. Do not skip anchors that are in the plan.

What You Read

  1. seed-plan.json — the anchors to create
  2. substrate.md — the shared problem surface (for context on what each anchor represents)

What You Produce

1. Anchor Files in Codespace

For each anchor in seed-plan.anchors[]:

  • Create the file at the specified path (relative to codespace root)
  • Include a module docstring explaining its purpose
  • Define the minimal interface (types, classes, functions) that sections will use
  • Mark everything as a stub — implementations come from sections

Example anchor (Python):

"""Shared error/result types for cross-section integration.

This module is owned by SIS (Shared Integration Substrate).
Sections extend these types; they do not redefine them.
"""

from dataclasses import dataclass
from typing import Any


@dataclass
class Result:
    """Standard result wrapper for cross-section interfaces."""
    success: bool
    data: Any = None
    error: str = ""

Example anchor (TypeScript):

/**
 * Shared error/result types for cross-section integration.
 * Owned by SIS. Sections extend, not redefine.
 */

export interface Result<T = unknown> {
  success: boolean;
  data?: T;
  error?: string;
}

Adapt the language and style to the project's conventions (read the codemap or existing code to determine the language and patterns).

2. Related-Files Update Signals

Read the full file on GitHub · 120 lines

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. yesterday First seen · 120 lines · 28 tokens per session scan A 533143a5ab60

Subscribe to this mod's changes

substrate-seeder is an agent published in the GitHub repository nestharus/agent-implementation-skill (3 stars, last pushed 1mo ago), licensed MIT. It adds 28 tokens to every session and 740 once invoked, about $0.0001 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 2026-09-03.