What is mock-endpoint?

A tool for describing and simulating external APIs, such as payment or mapping services, before connecting to the real ones.

It helps create API contracts, test data, mock servers, and integration wrappers, either from scratch or by scanning existing code.

It lets code and tests use predictable fake services, avoiding rate limits, authentication problems, side effects, and incorrect guesses about API data.

mock-endpoint — Skill for Claude Code and Codex by BostonOrange

Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo

git clone --depth 1 https://github.com/BostonOrange/claude-code-framework

agentmods

npx agentmods add skills/bostonorange/claude-code-framework/mock-endpoint

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/bostonorange/claude-code-framework/mock-endpoint/github.svg)](https://agentmods.dev/skills/bostonorange/claude-code-framework/mock-endpoint)

Your own site

<a href="https://agentmods.dev/skills/bostonorange/claude-code-framework/mock-endpoint"><img src="https://agentmods.dev/badge/skills/bostonorange/claude-code-framework/mock-endpoint/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/bostonorange/claude-code-framework/mock-endpoint"><img src="https://agentmods.dev/badge/skills/bostonorange/claude-code-framework/mock-endpoint.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 41 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 2,728 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 1 finding. 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	$0.00041	$0.02728
Opus 5.5	$0.00016	$0.01091
Sonnet 5.5	$0.00008	$0.00546
Haiku 4.5	$0.00004	$0.00273

Measured 1mo ago against content hash 91961cf838e9, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

mock-endpoint scanned grade A with 1 finding 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -s "https://api.example.com/endpoint?param=value" -H "Authorization: Bearer $TOKEN"

skills/mock-endpoint/SKILL.md · 357 lines

How it starts

The opening of the file, as written. The whole thing — 357 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Mock Endpoint

Define, mock, and test external API integrations safely. Creates a contract-first development workflow where external dependencies are fully described before any code touches a real service.

Usage

/mock-endpoint sl-transport-api           # Mock an external API from scratch
/mock-endpoint sl-transport-api departures # Mock a specific endpoint group
/mock-endpoint --from-code                # Scan codebase for existing API calls and generate mocks
/mock-endpoint --list                     # List all defined mocks

Why This Exists

When AI implements features that call external APIs:

It can't test against real services (rate limits, auth, side effects)
It may guess wrong about request/response shapes
Tests that hit real endpoints are flaky and slow
Wiring up incorrectly against production is dangerous

This skill creates a contract layer between your code and external services. The AI develops against the contract, tests against mocks, and the real service is only connected after human review.

Core Concepts

Contract File

The source of truth for what an external API looks like. Lives in .claude/skills/mock-endpoint/references/{service-name}.md.

Mock Fixture

Static request/response pairs generated from the contract. Used in tests.

Mock Server (optional)

A lightweight local server that serves mock responses. Used for manual testing and dev server integration.

Integration Wrapper

A thin abstraction layer around the external API call. In production it hits the real service; in tests it hits the mock.

Process

1. Define the Contract

If user provides docs or a URL, extract the API surface. If the API is already called in the codebase, scan for it.

Via Context7 (for known libraries/SDKs)

If the external service has an official SDK or client library, fetch documentation using the /fetch-docs skill pattern (resolve-library-id then get-library-docs) for endpoint signatures, auth patterns, and response shapes. Use fetched docs to populate the contract accurately instead of guessing.

Read the full file on GitHub · 357 lines

Files

What ships with it

1 file 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.

references/INDEX.md 355 B

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 First seen · 357 lines · 41 tokens per session scan A 91961cf838e9

Subscribe to this mod's changes

mock-endpoint is a skill published in the GitHub repository BostonOrange/claude-code-framework (3 stars, last pushed 3mo ago), licensed MIT. It adds 41 tokens to every session and 2,728 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Testing

research-engineer

An uncompromising Academic Research Engineer. Operates with absolute scientific rigor, objective criticism, and zero flair. Focuses on theoretical correctness, formal verification, and optimal implementation across any required technology.

davila7/claude-code-templates · 43 tokens

tika-eval-compare

Compare extracts from two Tika builds over a corpus to detect regressions in content, encoding, exceptions, and embedded-document handling. Use for "compare before/after extracts", "eval this change against the corpus".

apache/tika · 50 tokens

cua-driver

Use Cua Driver for desktop or browser tasks that are awkward or unavailable through Bash/APIs, or when the user explicitly wants GUI interaction: app testing, visual bug reproduction, form filling, calendar entry, screenshots, and demo recording. Also covers Cua setup; not OpenAI Codex Computer Use or web research.

davidondrej/skills · 68 tokens

mock-endpoint