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

No annotations are provided, so the description carries the full burden. It discloses that the tool only creates a URL and that a charge can occur only after user confirmation on Stripe. This prevents misinterpretation that the tool itself charges. It also warns against handling card details. Slightly more detail on URL expiry or idempotency would improve transparency.

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 then adding behavioral and usage context. Every sentence serves a distinct purpose with no wasted 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 output schema and no annotations, the description provides enough context for an agent to select and invoke the tool. It covers the primary behavior and safety. Minor omission: it doesn't mention that the URL is likely returned as output, but that is typical for such tools.

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 schema already provides detailed descriptions for both parameters (pack with pricing, batch_id with resumption behavior). The tool description adds no extra information beyond what's in the schema, so it meets the baseline of 3.

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 verb 'Create a hosted Stripe Checkout URL for a prepaid credit pack.' It specifies the resource (prepaid credit pack) and the action (create URL). This distinguishes it from sibling tools like create_screenshot_batch (different resource) and get_account_balance (read-only).

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 explicit usage guidance: 'Ask the user before calling it and never handle card details.' This clearly indicates when to use the tool (with user consent) and gives a safety rule. While it doesn't contrast with alternatives, the unique purpose and safety instructions make it clear.

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?

No annotations exist, so description carries full burden. It discloses that rendering happens in a real browser, the free tier limit, metering per network address, and that the batch pauses when credits are exhausted. However, it does not mention error conditions or what happens on failure, reducing transparency slightly.

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 cover the core action and key metering behavior. The most important action ('Render ... Returns batch id') is front-loaded. However, it could be slightly more structured by separating parameters from limitations, but overall it's efficient.

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 tool has 10 parameters and no output schema. The description omits the return format (beyond batch ID) and does not clarify which parameters are critical. For a complex batch creation tool, more detail on usage patterns (e.g., typical values, interaction between full_page and delay) would improve completeness.

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 60%; the description adds meter pricing context but does not improve understanding of individual parameters beyond what the schema already provides. For the 40% of parameters without schema descriptions (e.g., dark_mode, block_cookie_banners), the description offers no help, so it does not compensate.

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?

Description clearly states the tool renders web pages in a real browser and returns a batch ID. The verb 'render' and resource 'web pages' are specific. Sibling tools are distinct (e.g., get_screenshot_batch retrieves results, create_credit_checkout deals with payments), so no confusion.

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 polling via get_screenshot_batch ('Returns a batch id to poll') but does not explicitly state when to use this tool versus alternatives, e.g., when to use list_sample_captures instead. No when-not-to or exclusion criteria provided.

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 burden. It clearly indicates this is a read operation (no side effects) by specifying it returns credits and allowance. However, it does not disclose any potential latency or authentication requirements, though these are likely implicit.

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 sentence of 12 words, no filler, front-loaded with key information. Every word earns its place.

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 read-only tool with no parameters and no output schema, the description is fairly complete. It specifies what is returned and for whom. However, it does not detail the return format (e.g., data types, structure), which would be helpful given no output schema.

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 zero parameters, so schema coverage is 100%. Per guidelines, baseline for 0 params is 4. The description adds no parameter information, but none is needed.

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 'screenshot credits and free monthly allowance remaining' for the calling identity. It uses a specific verb ('get') and resource ('account balance'), and is distinct from sibling tools like 'create_credit_checkout' or 'get_screenshot_batch'.

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 usage for checking remaining credits/allowance, but does not explicitly state when to use this tool vs alternatives. No exclusion criteria or alternative tool references are provided, leaving the agent to infer context from tool names.

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?

No annotations provided, so the description carries the burden. It discloses it's a read operation that returns state, per-URL results, and download URLs after rendering. No destructive behavior mentioned, which matches expected read-only nature.

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?

Single sentence, no unnecessary words. Front-loaded and efficient.

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 output schema and no annotations, the description is adequate but could be more complete. It mentions state, per-URL results, and download URLs, but doesn't describe the state values or result structure.

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 only parameter 'id' is not described in the schema (0% coverage). The description adds 'created by this client', but lacks details on what the ID represents or format constraints. Schema includes pattern and examples, but description doesn't explain semantics.

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 reads state and per URL results of a batch, including download URLs after rendering. It distinguishes from sibling tools like create_screenshot_batch and list_sample_captures.

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 (use after creating a batch), but no explicit when-to-use or alternatives are given. Siblings suggest it's the read counterpart, but that's not stated.

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 full burden. It discloses that captures are public and refreshed on a schedule, and that no spending is involved. However, it does not detail behaviors like pagination, ordering, rate limits, or authentication requirements. The transparency is adequate for a simple list tool but could be more thorough.

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 only two sentences with no wasted words. The first sentence defines the resource and its dynamic nature; the second gives a clear use case. It is front-loaded and efficient.

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 and no annotations, the description provides essential context (public, refreshed, preview use) but omits return format, ordering, or any constraints beyond the limit. It is moderately complete for a simple list tool but could be improved by describing the output structure.

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 one parameter (limit) with default 12, max 100, min 1. Schema description coverage is 0%, so the description should add meaning but does not mention the parameter's purpose or behavior. The agent must rely solely on the schema, which is minimal. The description fails to compensate for the lack of schema documentation.

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 this tool lists public sample captures that are refreshed on a schedule. It identifies the resource ('public sample captures') and implies the action (listing). The mention 'before they spend anything' differentiates it from sibling tools like create_credit_checkout or get_screenshot_batch, which involve spending or specific batches.

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 suggests using this tool for previewing output before spending, which gives some context. However, it does not explicitly state when not to use this tool or mention alternatives like get_screenshot_batch for specific batches. The guidance is implied but lacks explicit exclusions or comparisons.

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