US Insider Trades (SEC Form 4) MCP

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

With no annotations, the description carries the burden and does disclose useful behavior: market-wide scope, last-N-days window, code-P-only filtering, and a value threshold. It omits auth/subscriber requirements (only visible from the access_token schema field), pagination, what max_filings does, and return format, leaving meaningful behavioral gaps.

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?

A single tight sentence that front-loads the core signal (open-market purchases, code P) and qualifies the scope. No filler or redundancy.

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?

For a 4-parameter, no-annotation, no-output-schema tool, the description covers purpose and the key filters but leaves max_filings behavior, result shape, and auth requirements unaddressed. Adequate but with clear gaps an agent would want filled.

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?

Schema description coverage is only 25% (just access_token), so the description should compensate more. It does clarify 'days' (last N days) and 'min_value_usd' (value threshold), but max_filings is never explained and access_token semantics come only from the schema.

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?

Clear verb (Scan) plus specific resource (Form 4 filings market-wide) and a precise filter (code P open-market purchases above a $ threshold). It is very easy to understand what the tool does, though it never references siblings insider_trades or watchlist to distinguish itself from them.

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 description frames the tool as the 'classic insider-buying signal,' which implies a use case (surfacing insider buys), and the 'PRO' marker hints at a paid tier. However, it gives no explicit when-to-use or when-not-to-use guidance and does not say how it differs from insider_trades.

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

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

With no annotations, the description carries the full load, and it does disclose useful traits: free, a 30-day recency window, a hard cap of top 3 results, and that buys/sells are parsed. It does not cover rate limits or data freshness beyond the window, but the key truncation behavior is disclosed.

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?

A single dense sentence with no waste; the free/no-auth signal is front-loaded and the scope, time window, and result cap all land in one pass.

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?

For a one-parameter lookup with no output schema, the description supplies the essential missing pieces: result count, time range, and content of results (parsed buys/sells). Only matching behavior for the name input is left unclear.

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?

Schema coverage is 100% and the single 'company' parameter already says 'Company or insider name, e.g. Tesla'. The description's 'company or person name' restates that rather than adding format, matching, or ambiguity-resolution guidance.

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?

States a specific resource (SEC Form 4 insider filings) and the retrieval verb (latest, for a company or person). It does not explicitly contrast with buy_scanner or watchlist, but the subject matter is distinct enough that disambiguation is mostly implicit.

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?

Usage is implied by the 'latest filings for name X' framing, and the 30-day window hints at a quick-lookup use case. There is no explicit statement of when to prefer this over buy_scanner, nor any exclusion or precondition.

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

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

With no annotations, the description must carry the load, and it does disclose several real traits: a paid/PRO tier requirement, a hard cap of 15 companies, and that results are aggregated (net buy/sell) rather than raw transactions. It omits error behavior for unknown tickers, how the 15-item limit is enforced, and whether partial day ranges are honored.

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?

One compact sentence, front-loaded with the tier marker and the resource, followed by the constraints. No filler.

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?

For a 3-parameter tool with no output schema and no annotations, the core semantics are present, but the absence of guidance on how the summary is shaped (per company? combined?) and on failure modes for invalid tickers leaves meaningful gaps.

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?

Schema coverage is only 33% (only access_token is documented in the schema), so the description has to compensate, and it does: it pins down that companies accepts names or tickers and caps at 15, and that days defines the lookback window. The access_token flow is already covered by the schema. This is meaningfully beyond the schema, though it doesn't state a default for days.

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 a specific verb-implied resource: insider activity across a set of companies, aggregated into net buy/sell value. It conveys scope (up to 15 companies, N days) that makes it feel distinct from a raw trade feed, but it never names buy_scanner or insider_trades, so it does not actively differentiate from siblings.

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?

"PRO." hints at a paid/subscriber gate but there is no when-to-use guidance, no mention of the alternative sibling tools, and no stated prerequisites beyond the implicit auth. An agent has to guess whether this or insider_trades is the right call.

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