Skip to main content
Glama

Equibles

by io.github.daniel3303
OverviewDiscussionsAdmin

Top Institutional Holders

GetTopHolders
Read-only

Get the top institutional holders (fund managers) of an exact stock or ETF listing from SEC 13F-HR filings. Returns a ranked list by shares held, including published position value and percentage of total institutional 13F shares (not of shares outstanding). Values normally use report-date closing prices, may fall back to filer values, and can be zero when unavailable. During the newest quarter's filing window, non-ETF primary stocks carry non-filers' prior-quarter positions; ETF listings remain exact and as-filed because carry-forward is filer-wide. Use position type before treating put/call rows as ownership.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
offsetNoNumber of ranked holding rows to skip before returning results (default: 0)
tickerYesListed security ticker (e.g., AAPL, VOO)
maxResultsNoMaximum number of holding rows to return (default: 20, clamped to 1-500)
reportDateNoQuarter-end 13F report date in YYYY-MM-DD format, e.g. 2026-03-31 (defaults to the latest available; an off-quarter date snaps to the nearest report on or before it)

Schema Changelog

Changes observed during successful MCP inspections.

  1. Changed1 schema field changed
    • changedInput schema / properties / ticker / description
      Previous value: -"Company ticker symbol (e.g., AAPL, MSFT)"New value: +"Listed security ticker (e.g., AAPL, VOO)"
  2. Changed2 schema fields changed
    • changedInput schema / properties / maxResults / description
      Previous value: -"Maximum number of holders to return (default: 20, clamped to 1-500)"New value: +"Maximum number of holding rows to return (default: 20, clamped to 1-500)"
    • addedInput schema / properties / offset
      Added value: +{
+  "default": 0,
+  "description": "Number of ranked holding rows to skip before returning results (default: 0)",
+  "type": "integer"
+}
  3. First observed

TDQS

A4.5/5.0
Behavior5/5

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

Annotations only indicate read-only and non-destructive behavior, so the description carries the burden of explaining data nuances. It adds substantial context: percentage is of total institutional 13F shares, prices may fall back to filer values, values can be zero, non-ETF stocks may carry prior-quarter non-filer positions, and put/call rows must be treated carefully.

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

Conciseness5/5

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

The description is structured logically: purpose, return content, valuation behavior, quarter-window caveat, and position-type warning. Every sentence earns its place, with no filler or redundancy.

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?

There is no output schema, and the description adequately explains what the ranked list contains, the key fields, price fallback behavior, zero-value cases, and important filing-window exceptions. This is sufficient for an agent to understand what to expect and how 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 baseline is 3. The description reinforces that the ticker must be an exact listed security, but it does not materially add parameter semantics beyond what the schema already documents.

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?

The description states a specific action and resource: getting the top institutional holders (fund managers) of an exact stock or ETF listing from SEC 13F-HR filings, ranked by shares held. This clearly differentiates it from related tools like institutional ownership history, funds holding a stock, or top buyers/sellers.

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?

It gives clear context: the tool is for exact stock or ETF listings, not fuzzy searches, and includes important caveats about the newest quarter's filing window and put/call position types. It does not explicitly name alternative tools or state when not to use it, so it falls short of a 5.

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

All Equibles toolsInspect
Try in Browser
One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Glama MCP Gateway

Add one secure layer between your agents and this server.

Resources