alpha402x Equity Research

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

Annotations declare readOnlyHint=true, which aligns with the description stating it is a free check with no charge. The description adds behavioral context beyond annotations by explaining what the response includes: confirmation of coverage, fiscal periods (newest first), and payable URLs. This informs the agent that it is safe to call and what data to expect.

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 a single, well-structured sentence that front-loads the core purpose ('Free coverage check against SEC EDGAR for any U.S. ticker'), then efficiently details outputs and pricing. Every word serves a purpose with no redundancy or 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?

The description is contextually complete given the tool's simplicity (2 parameters with full schema coverage) and absence of an output schema. It explains what the tool returns: confirmation of coverage, sorted fiscal periods, and payable URLs. It also addresses pricing, ensuring the agent understands it is free and safe.

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 100% description coverage for both parameters. The tool description adds slight value beyond the schema by stating that the tool 'lists available fiscal periods (newest first)', implying that omitting the period parameter returns all periods. This provides context not fully captured in the schema's description of the period parameter.

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 clearly defines the tool's purpose: 'Free coverage check against SEC EDGAR for any U.S. ticker'. It specifies the action (check coverage), resource (SEC EDGAR, ticker), and outputs (confirms coverage, lists periods, returns URLs). It implicitly distinguishes from sibling tools like 'get_product_terms' and 'how_to_pay_x402' which relate to payment and research listing, not coverage checking.

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 provides clear usage context: it is a free coverage check before paying for extraction. It states 'No charge; the paid product is the extraction itself', guiding the agent to use this tool to verify coverage. It does not explicitly list when not to use or alternatives, but the sibling tools are distinct enough that confusion is unlikely.

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?

The description adds clarity beyond the readOnlyHint annotation by explaining that the tool returns constants mirroring the payment gates and that the live 402 header is authoritative. This reveals the tool's non-authoritative, read-only nature without contradicting annotations.

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 two sentences, front-loading the core purpose and providing essential context without redundancy or extraneous detail.

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 simple tool with one parameter, the description adequately explains what the tool does and its relationship to the authoritative document. However, it could benefit from briefly describing the output format, though no output schema is present.

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 already describes the 'product' parameter with examples at 100% coverage. The description does not add new parameter information, so it meets the baseline for high schema coverage without improvement.

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 clearly states the tool retrieves exact x402 payment terms for a specific product path or URL, listing the fields (price, asset, network, payTo, scheme). This distinguishes it from sibling tools like check_10q_coverage and list_research, which serve different purposes.

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 implies this tool is for fetching payment terms, but it does not explicitly state when to use it versus alternatives. The mention of 'mirrors the same constants the gates are built from' provides some context, but lacks direct comparative guidance.

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?

Annotations declare readOnlyHint=true, and the description accurately reflects this by indicating the tool provides informational content. It adds value by detailing the specific topics covered (payment flow, libraries, terms) beyond the annotation, with no contradiction.

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 a single, efficient sentence. However, the vague 'these products' could be clarified without adding length. Overall, it is well-structured and front-loaded with key content.

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?

Given no output schema, the description adequately lists topics but lacks specificity about which products are covered. This omission may require the agent to have external context. It is moderately complete but not fully self-contained.

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?

There are no parameters, so schema coverage is 100%. The description adds meaning by explaining what the tool returns when invoked, which suffices for a parameterless tool. Baseline 4 applies.

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 clearly states the tool provides x402 payment flow, client libraries, and authoritative terms location. However, the phrase 'these products' is ambiguous without further context, slightly reducing clarity. It effectively distinguishes from siblings like check_10q_coverage or get_product_terms.

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 provides no guidance on when to use this tool versus siblings. No explicit conditions, exclusions, or alternatives are mentioned, leaving the agent to infer usage context from the title alone.

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?

Adds specifics about output (products, prices, URLs, free guides, USDC pricing) beyond the readOnlyHint annotation. No contradictions.

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 efficient sentences, front-loaded with main purpose, no unnecessary words.

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?

Given no parameters or output schema, description fully explains what the tool returns: research products, prices, URLs, free guide pages, and pricing currency.

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?

No parameters exist, so baseline is 4. Description adds context about the output, compensating for lack of parameters.

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?

Describes listing the full catalog of research products with prices and URLs, using the verb 'list'. Distinguishes from sibling tools that check specific coverage or payment info.

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?

Implies use for general catalog listing, with sibling tools covering more specific functions. Lacks explicit when-not or alternatives, but context is clear.

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