Equibles

Funds Holding a Stock

GetFundsHoldingStock

Read-only

Get the registered investment companies (mutual funds and ETFs) holding an exact stock or ETF listing, from SEC Form NPORT-P portfolio reports. The listed security's authoritative CUSIP (or, for a listing on another exchange written MIC:TICKER, its ISIN) is matched against the holding rows on each fund series' most recent report (series that stopped filing more than 18 months ago are excluded), so an exited position never shows as current. Returns the fund's registrant and series, the reporting period, the position size, its U.S.-dollar value, its share of the fund's net assets and the payoff profile (Long/Short), largest positions first. Report dates differ per fund series (each files on its own fiscal quarter), so values are as of each row's report date and cross-row totals mix as-of dates.

Input Schema

Name	Required	Description
`offset`	No	Number of matching fund positions to skip before returning rows (default: 0)
`ticker`	Yes	Listed security ticker (e.g., AAPL, VOO); a listing on another exchange is MIC:TICKER (XPAR:AIR).
`maxResults`	No	Maximum number of fund positions to return, largest first (default: 20, clamped to 1-500)
`registrantOrSeries`	No	Optional registrant or series name filter (case-insensitive contains, e.g. 'Vanguard') — reaches positions beyond the largest 500

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedOct 15, 2026

changedInput schema / properties / ticker / description

Previous value: -"Listed security ticker (e.g., AAPL, VOO)"New value: +"Listed security ticker (e.g., AAPL, VOO); a listing on another exchange is MIC:TICKER (XPAR:AIR)."

Changed1 schema field changedSep 4, 2026

changedInput schema / properties / ticker / description

Previous value: -"Stock ticker symbol (e.g., AAPL, MSFT)"New value: +"Listed security ticker (e.g., AAPL, VOO)"

Changed1 schema field changedSep 3, 2026

addedInput schema / properties / offset

Added value: +{
+  "default": 0,
+  "description": "Number of matching fund positions to skip before returning rows (default: 0)",
+  "type": "integer"
+}

First observedJul 19, 2026

TDQS

A4.4/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already cover the safety profile (readOnly, non-destructive, non-openWorld), and the description adds substantial behavior: the matching key, the 18-month filing exclusion so exited positions don't appear current, largest-first ordering, and the caveat that report dates differ per series so cross-row totals mix as-of dates.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Purpose and data source are front-loaded, and each subsequent clause earns its place (matching, exclusion, returned fields, date caveat). It is dense and long for a single paragraph, but nothing is redundant or padded.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description carries the return burden and does so: registrant/series, reporting period, position size, dollar value, share of net assets, payoff profile, and ordering. Combined with the as-of-date caveat, an agent has everything needed to interpret results.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents offset, ticker, maxResults and registrantOrSeries. The description adds only minor value (confirming largest-first ordering and the MIC:TICKER/ISIN matching form), so the baseline of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource — registered investment companies (mutual funds/ETFs) holding an exact stock/ETF listing — with the data source named (SEC Form NPORT-P). This clearly separates it from siblings like GetEtfHoldings (holdings OF a fund) and GetTopHolders (13F institutional holders), so an agent can pick it without opening a schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives clear context for when it applies: an exact listed security, matched by authoritative CUSIP/ISIN against each fund series' most recent report. It does not, however, explicitly name alternatives or state exclusions (e.g. use GetTopHolders for 13F institutions), so it stops short of full routing guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

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