speckit.harness.verify

speckit.harness.verify is a command for Claude Code from formin/spec-kit-harness. It costs 18 tokens per session (985 once invoked), scanned A, original, MIT.

A command that checks important claims in specification and planning documents against primary sources, then records each result as a verification record. A primary source is the original documentation, paper, dataset, or other direct evidence.

In plain words
What is it for?
Use it to verify claims in spec.md, plan.md, and unverified critical research entries within an initialized harness.
Why use it?
It distinguishes facts that were checked from assumptions, so later design and implementation decisions can rely on a visible record of what is supported.

Command for Claude Code

Written for Claude Code: $ARGUMENTS substitution.

Good fit Use it to verify claims in spec.md, plan.md, and unverified critical research entries within an initialized harness.

Compare 6 commands from other repositories ↓
Install with agentmods
npx agentmods add commands/formin/spec-kit-harness/speckit.harness.verify
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.

Clone the repo
git clone --depth 1 https://github.com/formin/spec-kit-harness

Made for: Claude Code.

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 speckit.harness.verify

README.md
[![agentmods](https://agentmods.dev/badge/commands/formin/spec-kit-harness/speckit.harness.verify.svg)](https://agentmods.dev/commands/formin/spec-kit-harness/speckit.harness.verify)
Your own site
<a href="https://agentmods.dev/commands/formin/spec-kit-harness/speckit.harness.verify"><img src="https://agentmods.dev/badge/commands/formin/spec-kit-harness/speckit.harness.verify.svg" alt="Measured on agentmods" height="20"></a>
Per session 18 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 985 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00018 $0.00985
Opus 5 $0.00009 $0.00492
Sonnet 5 $0.00004 $0.00197
Haiku 4.5 $0.00002 $0.00098

Measured 8d ago against content hash a31227d46c53, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

speckit.harness.verify 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 8d 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.

commands/speckit.harness.verify.md · 94 lines

How it starts

The opening of the file, as written. The whole thing — 94 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Claim Verification

Turn unexamined assertions into verification records. Following Harness-1 (arXiv:2606.02373), verification is part of the externalized harness state: every checked claim leaves a durable record with a verdict, a method, and an evidence pointer — so later phases (and later sessions) know what is proven, what is refuted, and what is merely assumed.

User Input

$ARGUMENTS

Optional. May name target artifacts (e.g. plan.md, spec.md, curated) and/or specific claims to check. Default targets: the active feature's spec.md and plan.md, plus all critical-importance entries in curated.md that have no verification record yet.

Prerequisites

Resolve HARNESS_DIR as in /speckit.harness.init. Require an initialized harness (budget.md present) — otherwise instruct the user to run /speckit.harness.init and stop. Load the verification budget (Remaining in budget.md) and existing verification.md records.

Steps

1. Extract claims

Read the target artifacts and extract load-bearing factual claims: statements about the codebase, dependencies, APIs, data, or environment that, if wrong, would change the design or break the implementation. Typical shapes: "X is handled by Y", "library Z supports W", "there is no existing implementation of V", "endpoint U returns T".

Exclude: requirements (decisions, not facts), pure opinions, and claims that already have a verified record at high confidence in verification.md (re-verify only if the user asks, or the underlying source changed).

Rank claims: critical curated links and architectural assumptions first. Cap the list at the remaining verification budget; say explicitly which claims were deferred for budget reasons.

2. Verify each claim — adversarially

For each claim, in rank order:

  1. Try to refute it, not confirm it. Ask: what would be true if this claim were false? Check that.
  2. Go to the primary source — open the actual file/API/doc at its current state. Never accept the curated summary or the artifact's own citation as proof; evidence.md tells you where to look, not what is true.
  3. Decide the verdict:
    • verified — the primary source confirms it now, and your refutation attempt failed.
    • refuted — the primary source contradicts it (record what is actually true).
    • unverifiable — cannot be checked with available access/budget (record what would be needed). Assign confidence high | medium | low.
  4. Record a row in verification.md (claim, method — e.g. "re-read src/auth/session.ts:40-80", verdict, confidence, evidence ID, date). Add or update the evidence.md entry so the record has a pointer. Decrement the verification budget and append an action-log row in budget.md.
  5. Propagate refutations: if a curated entry is refuted, change its importance row in curated.md to refuted (see V-xxx) — do not delete it; a recorded dead end prevents re-deriving the same error later.

Read the full file on GitHub · 94 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. 8d ago First seen · 94 lines · 18 tokens per session scan A a31227d46c53

Subscribe to this mod's changes

speckit.harness.verify is a command published in the GitHub repository formin/spec-kit-harness (5 stars, last pushed 2mo ago), licensed MIT. It adds 18 tokens to every session and 985 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 2026-08-31.