get_sharesCommon shares outstanding (latest + history) and public float for a ticker, from the SEC XBRL cover-page tags. Shares outstanding updates every 10-Q/10-K; public float is reported on the 10-K cover. The inputs for market-cap and free-float math.
| Name | Required | Description | Default |
|---|---|---|---|
| ticker | Yes | US stock ticker, e.g. 'AAPL'. | |
| history | No | Include the full reported history (default false). |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false. The description adds value beyond those by disclosing the exact source (SEC XBRL cover-page tags) and the update cadence (shares outstanding at every 10-Q/10-K; public float on the 10-K cover). It does not describe return formatting, but given the annotations cover safety, this is a minor gap.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two sentences, each carrying distinct information: what is returned, the data source and refresh behavior, and the intended use case. No filler; key terms are front-loaded.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
With only two simple parameters and safety-related annotations, the description covers the essential semantics: source, freshness, and use case. The lack of an output schema is mitigated by explicitly listing what is returned. Some format details are unspecified, but the tool is simple enough that this is not a serious gap.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema fully documents both parameters (ticker and history), so the description does not need to compensate. It reinforces the history option by mentioning 'latest + history' but adds no syntax or formatting details beyond the schema. Baseline 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description names the resource precisely ('common shares outstanding (latest + history) and public float') and identifies the SEC XBRL cover-page tags as the data source, which helps distinguish it from broader siblings like get_fundamentals or get_xbrl. However, it does not explicitly differentiate itself from any sibling by name, so it falls just short of full distinction.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The final sentence states the intended use case ('The inputs for market-cap and free-float math'), giving agents a concrete reason to select this tool. It does not mention when not to use it or name alternative tools, but the context is clear enough for a dedicated shares tool.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.