Tool sets & discovery

How Particle tools are grouped into exposure categories, how the include/exclude selectors shape your tools/list, and why every public tool stays callable by name.

Every Particle MCP tool belongs to exactly one exposure category. Categories are the unit of tools/list advertisement: some advertise on a bare connection (default), others only when you ask for them (opt-in). But the advertisement is just a menu — every public tool is always callable by name, no matter what was advertised. Discovery is free; execution is metered and plan-gated.

Categories

Category	Exposure	Summary
system	always on	Discovery meta-tools: browse the full tool catalog and call any tool by name.
podcasts	default	Resolve podcasts, list and fetch episodes, search transcripts, and find entity mentions.
people	default	Resolve people and entities to canonical handles and fetch person profiles.
companies	default	Resolve companies and fetch company profiles with people, products, and competitors.
topics	default	Browse the hierarchical topic taxonomy used to classify podcast episodes.
podcast_rankings	default	Podcast chart rankings: current charts, movers, and ranking history.
podcast_guests	default	Podcast guest directory, trending guests, and per-guest appearance profiles.
podcast_advertising	opt-in	Podcast advertising intelligence: sponsor rosters, ad presence, and sponsor leaderboards.
podcast_publishers	opt-in	Podcast publisher profiles with their shows, bias profile, and suitability profile.
podcast_ratings	opt-in	Listener review ratings for podcasts: summaries and recent rating lists.
podcast_bias	opt-in	Corpus-wide political-bias views: publisher leaderboards and publishers by bias result.
podcast_suitability	opt-in	Corpus-wide GARM brand-suitability views: publisher leaderboards and category exposure.

A bare connection advertises system plus every default category. The five opt-in categories advertise only when selected.

Selecting categories

The selector lives on the connection — it shapes what tools/list advertises, nothing else.

Query parameters

Append ?include= (and/or ?exclude=) to the connection URL. Values are comma-separated category names, case-insensitive.

# Advertise the opt-in advertising + bias categories on top of the defaults.
https://mcp.particle.pro?include=podcast_advertising,podcast_bias

# Advertise everything.
https://mcp.particle.pro?include=all

# Hide a default category you don't want cluttering the list.
https://mcp.particle.pro?exclude=podcast_rankings

# Combine: add an opt-in category, drop a default one.
https://mcp.particle.pro?include=podcast_ratings&exclude=topics

• include=all selects every declared category.
• The active set is computed as defaults ∪ include − exclude.
• Unknown tokens are ignored — a typo in a selector never errors tools/list; you just see the default surface for that token.
• system is irremovable — exclude=system is silently ignored, so the discovery meta-tools never disappear.

Headers

Clients that can’t append query strings can send the same values as headers:

X-Particle-Include: podcast_advertising,podcast_bias
X-Particle-Exclude: podcast_rankings

The query parameter wins when both are present (query > header precedence), resolved independently for each direction (include and exclude).

Selecting exact tools

When a category is still too broad — a curated workflow that needs exactly four tools, say — the ?tools= selector pins tools/list to a comma-separated list of tool names:

# Advertise exactly these tools (plus the always-on system meta-tools).
https://mcp.particle.pro?tools=particle_podcast_resolve,particle_podcast_search_transcripts,particle_podcast_get_episode

• A non-empty ?tools= selection overrides include/exclude entirely.
• Named tools advertise regardless of category exposure — an opt-in tool named here shows up without its category.
• The system meta-tools are always advertised alongside the selection, so discovery never disappears.
• Unknown names are ignored; if every name is unknown, the selection is empty and the connection falls back to the category selectors above (defaults ∪ include − exclude).
• Same header fallback (X-Particle-Tools) and query-over-header precedence as the category selectors.
• And the same contract: this shapes advertisement only — every public tool stays callable by name.

This is the mechanism behind the pre-built skill bundles: each skill embeds a ?tools= URL so the agent sees only the tools its workflow needs.

Every public tool is callable by name

The selector only governs the menu (tools/list). tools/call is selector-independent: every public tool stays executable by name whether or not it was advertised on your connection.

That separation is deliberate:

• Discovery is free. A bare connection can learn the entire surface via particle_catalog and call any of it — no reconnection, no selector change.
• Execution is metered and plan-gated. Calling a tool runs the same billing meter, pricing gate, and premium-tier gate regardless of how you reached it. Advertisement changes visibility, never entitlement.

So the opt-in categories exist to keep a default agent’s tool list focused, not to lock anything away. If your harness lets you call tools it didn’t see advertised, just call them. If it doesn’t, use the meta-tools below.

Meta-tools

Two always-on system tools make the surface self-expanding.

particle_catalog

Browse the full catalog. No arguments → the category menu; with a category → full input schemas for that category’s tools.

particle_call

Dispatch any public tool by name — the fallback for harnesses that block un-advertised tool names.

particle_catalog

# See every category and its tools.
particle_catalog {}

# Get the full input schema for an opt-in category before calling it.
particle_catalog { "category": "podcast_bias" }

particle_call

# Reach an opt-in tool when the harness blocks un-advertised tool_use names.
particle_call {
  "tool": "particle_podcast_get_bias_leaderboard",
  "arguments": { "metric": "most_right_leaning", "limit": 10 }
}

Identical metering and plan gating apply whether you call a tool directly or through particle_call.

Next steps

Tool reference

Every tool, grouped by category, with inputs and outputs.

Quickstart

Connect a client and run a first call.