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

No annotations are present, so the description carries the full burden. It does disclose that the tool is free and mentions a PayTo address, but it does not explain what kind of schema is returned, whether any authentication is needed, or what access constraints exist. The payment address is also confusingly placed for a tool described as free.

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?

The description is short and front-loaded with 'Free', but it includes a PayTo address that is not clearly relevant to retrieving a free schema. The extra payment details add noise without strengthening the tool's purpose.

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 no annotations and no output schema, the description should clarify what the returned schema looks like and what exactly it covers. It names the AAPL fact and URL, but it does not state the schema format, structure, or whether this tool only ever returns schema for that hardcoded fact. This leaves an agent guessing about the actual return value.

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 input schema has zero parameters and schema description coverage is 100%, so there is no parameter meaning for the description to add. A baseline of 4 is appropriate for a no-parameter tool.

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 identifies the tool as providing a schema for a specific fact (AAPL) and gives a direct URL, so an agent can infer it returns schema information rather than fact data or search results. However, it lacks an explicit verb like 'returns' or 'fetches', and the Free/PayTo phrasing introduces slight ambiguity about what the tool actually does.

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?

There is no explicit guidance about when to call get_schema versus the sibling tools fetch_fact or search_facts. The 'Free' versus 'paid AAPL filing fact' wording implies a cost-based distinction, but the description never states that get_schema should be used instead of fetching the paid fact.

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