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.
npx skills add cyanheads/obsidian-mcp-server --skill add-toolgit clone --depth 1 https://github.com/cyanheads/obsidian-mcp-serverWrote 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.
[](https://agentmods.dev/skills/cyanheads/obsidian-mcp-server/add-tool)<a href="https://agentmods.dev/skills/cyanheads/obsidian-mcp-server/add-tool"><img src="https://agentmods.dev/badge/skills/cyanheads/obsidian-mcp-server/add-tool/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.
<a href="https://agentmods.dev/skills/cyanheads/obsidian-mcp-server/add-tool"><img src="https://agentmods.dev/badge/skills/cyanheads/obsidian-mcp-server/add-tool.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Agent Snooping · line 686 Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
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 | $0.00035 | $0.17726 |
| Opus 5.5 | $0.00014 | $0.07090 |
| Sonnet 5.5 | $0.00007 | $0.03545 |
| Haiku 4.5 | $0.00003 | $0.01773 |
Grade A, and why
add-tool 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 today.
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.
const articles = await fetch(input.pmids); Copies of this mod
8 near-identical copies found in the catalogue:
- add-tool — 100% identical, 22 lines differ
- add-tool — 100% identical, 4 lines differ
- add-tool — 100% identical, 22 lines differ
- add-tool — 100% identical, 22 lines differ
- add-tool — 100% identical, 22 lines differ
- add-tool — 100% identical, 22 lines differ
- add-tool — 100% identical, 22 lines differ
- add-tool — 100% identical, 22 lines differ
How it starts
The opening of the file, as written. The whole thing — 903 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Context
Tools use the tool() builder from @cyanheads/mcp-ts-core. Each tool lives in src/mcp-server/tools/definitions/ with a .tool.ts suffix. The standard registration pattern uses a definitions/index.ts barrel that collects all tools into an allToolDefinitions array for createApp(). Fresh scaffolds from init start with direct imports in src/index.ts — the barrel is introduced as definitions grow. Match the pattern already used by the project you're editing.
Steps
- Gather the tool's name, purpose, and input/output shape from the user's request — ask only if genuinely absent
- Determine if it needs input the caller may not supply — a confirmation, a choice, the client's roots — which makes it a multi-round-trip handler (
ctx.requestInput/ctx.inputs, seeapi-context) - Create the file at
src/mcp-server/tools/definitions/{{tool-name}}.tool.ts - Register the tool in the project's existing
createApp()tool list (directly insrc/index.tsfor fresh scaffolds, or via a barrel if the repo already has one) - Run
bun run devcheckto verify — it applies Biome's formatting fixes as it runs - Smoke-test with
bun run rebuild && bun run start:stdio < /dev/null(orstart:http) — theCore services constructedlog record must list the new tool in itstoolsfield (the message text shows only counts); if it doesn't, the tool never reachedcreateApp()
Naming
Tools use lowercase snake_case with a canonical server/domain prefix, {server}_{verb}_{noun} by default. Drop the noun only when the verb is a complete action on its own (git_pull, git_status): if {server}_{verb} leaves "…what?" unanswered — search what? connect to what? — the noun is missing. The full rule is the Name row of the design-mcp-server Design table.
Examples: pubmed_search_articles, pubmed_fetch_fulltext, clinicaltrials_find_eligible.
The server prefix is judged on clarity, not length: the brand name or the plain well-known word for the domain both pass (pubmed_, patents_); an abbreviation fails only when it reads as something else out of context (loc_, ct_). A fourth segment is fine when the noun is inherently two words (openfda_search_device_clearances). When a name resists the schema — can't pick a verb, noun feels generic, the verb wants a second word — that's usually a signal the scope is fuzzy; split the tool, rename, or reconsider.
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.
- today Changed · +8 lines 9210f47a1f51
- 19d ago Changed · +13 lines 8bda9da26197
- 1mo ago Changed · +46 lines 95ce1591e082
- 1mo ago Changed c8767dc3d4c2
- 1mo ago Changed · +32 lines fd95655dd297
- 1mo ago Changed 462500c4815a
- 1mo ago First seen · 804 lines · 35 tokens per session scan A 5ba100b246b6
add-tool is a skill published in the GitHub repository cyanheads/obsidian-mcp-server (701 stars, last pushed today), licensed Apache-2.0. It adds 35 tokens to every session and 17,726 once invoked, about $0.0001 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 2026-08-30.
Other skills, from other repositories
widget-authoring
Author or edit ThinkEx widgets, which are self-contained interactive HTML blocks inside documents. Use when the user explicitly asks for a widget, asks for interaction or live computation, or wants a document visual that ordinary blocks cannot express.
pkm-session-end
Use when wrapping up a work session — creates devlog entry, captures undocumented decisions/research/debugging, audits link health of session work, and updates project index. Primarily used via the pkm-capture agent.
pkm-write
Use when writing to the vault — creating new notes (vaultwrite), editing existing notes (vaultedit, vaultappend, vaultupdatefrontmatter). Handles duplicate checking, link discovery, annotations, and index updates for new notes. Provides guidelines for modifications.
pkm-explore
Use when researching what the vault knows about a topic — performs graph + semantic exploration with gap analysis to map existing knowledge and find missing connections. Primarily used via the vault-explorer agent. Not for routine session-start context loading (hooks handle that).
triage-tasks
Use when you want to review and batch-update open vault task statuses for the current project or across all projects.
tackle-task
Use when starting work on a specific vault task, when a task title or path is mentioned, or when coming from triage output.