Menor Preço Hoje - MPH

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 does disclose the data source, the geographic scope, and that the price is current ('vigente'). However, it does not describe the return shape, no-result behavior, or any limitations, which would be useful given the absence of an output schema.

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 concise sentences with no filler. The core action and scope are front-loaded, followed by a practical usage trigger. 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?

The description covers what the tool does, where it applies, and when to use it. However, with no annotations and no output schema, it fails to specify what the response contains (e.g., store, price, date) or what happens when no matching price is found, which leaves a noticeable gap for an agent.

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 100%, and the schema already documents the 'product' parameter with an example. The description adds contextual framing (Lages, lowest current price) but no additional parameter-level semantics beyond what the schema provides.

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 uses a specific verb ('Encontra') and names the exact resource: the current lowest price of a product in Lages, Santa Catarina, from a defined data source. It clearly communicates what the tool does and is conceptually distinct from the sibling tools, though it does not explicitly contrast itself with 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 gives an explicit trigger: 'Use quando o usuário perguntar onde determinado produto está mais barato.' This is clear and actionable. It does not mention when not to use the tool or name alternatives, so it stops short of a perfect score.

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 disclosure burden. It usefully discloses that only current/valid offers ('ofertas vigentes') and only supermarkets accompanied by the service are considered. It does not describe output structure, ordering, or matching behavior, but these are minor gaps for a read-only comparison tool.

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, compact sentence that front-loads the core action and includes geographic and scope constraints without any filler or repetition.

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 is simple, with one fully documented parameter, so the description is mostly adequate for invoking it. However, without an output schema or sibling routing, it does not specify what the returned comparison contains or how this tool differs from search_offers/top_offers, leaving some gaps in contextual 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 coverage is 100%: the single parameter 'product' already has a description ('Produto que será comparado entre mercados'). The tool description adds no additional semantic detail beyond what the schema provides, so the baseline score 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 uses a specific verb ('Compara') and a clear resource: current offers of a product across supermarkets tracked by Menor Preço Hoje in Lages, SC. This distinguishes it from siblings like best_price or list_markets without merely restating the tool name.

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 intended use case is implied: when an agent needs to compare a product's current offers across supermarkets. However, there is no explicit guidance on when to prefer this tool over siblings like search_offers, top_offers, or best_price, and no exclusions are 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?

No annotations are provided, so the description carries full responsibility for behavioral disclosure. It only states that the tool lists markets, implying a read-only operation, but does not disclose output format, ordering, filtering, or any side effects. For a no-parameter tool this is minimal disclosure.

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 concise sentence, front-loading the action 'Lista' followed by the object. It contains no redundant or extraneous information, and the location qualifier adds useful context.

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 is simple (no parameters) and the description includes the program and geographical scope, which is helpful. However, with no output schema, the description does not indicate what the returned market entries look like (names, objects, ordering). For a list tool, this is a notable gap, though not severe for a no-arg call.

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, so there are no parameter descriptions to assess. Per the rubric, a tool with 0 parameters gets a baseline of 4; the description doesn't need to compensate for missing parameter docs.

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's purpose: listing the markets tracked by Menor Preço Hoje in Lages, SC. The verb 'Lista' identifies the action and the resource 'mercados' is specific. It is distinguishable from the siblings, which focus on offers/prices, though it doesn't explicitly name 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?

No guidance is given on when to use this tool versus alternatives like search_offers or top_offers. The description only states what the tool does, not its intended usage context or exclusions. An agent must infer that market listing is different from offer pricing.

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 are provided, so the description carries the full burden. It adds useful context by specifying that offers are current ('vigentes') and scoped to a local source and region. However, it does not disclose output format, ordering, or limitations, though this is a relatively minor gap for a simple search tool.

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 one compact, front-loaded sentence that states the core purpose and gives usage guidance without filler. Every part 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 one-parameter tool, the description covers the input and trigger conditions well. However, there is no output schema and four sibling tools, so it would benefit from explaining what the result looks like and how it differs from top_offers, best_price, and list_markets. The broad mention of 'supermercados locais' may also blur the line with list_markets.

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 describes the single 'query' parameter, including examples, so schema coverage is 100%. The description adds little parameter-specific meaning beyond that, so the baseline score of 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 clearly states the tool's action ('Busca ofertas vigentes') and its scope: current offers from Menor Preço Hoje in Lages, Santa Catarina. It is specific and unambiguous, though it does not explicitly name or distinguish sibling tools.

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 gives explicit when-to-use guidance: whenever the user asks about products, prices, promotions, or local supermarkets. It does not provide when-not-to-use conditions or contrast with alternatives like list_markets or best_price.

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 are provided, so the description carries the burden. It usefully discloses that the offers are current ('vigentes') and location-scoped, and 'Retorna' implies a read operation. Still, it does not explain how 'principais' is determined, whether results are paginated, or how fresh the data is — acceptable but not rich.

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 compact sentence with no filler. It front-loads the action and includes only meaningful details: source, recency, and geographic scope.

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 parameterless tool with no output schema, the description gives enough context to decide to invoke it: it returns current top offers from a named source in a named city. It would be fully complete if it defined what 'principais' means (e.g., by price, popularity, or recency), but invocation itself requires no further information.

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 full schema coverage, so there is nothing for the description to add about parameter meaning. For a 0-parameter tool, the baseline is 4, and the description's contextual scope (Lages, Santa Catarina) reinforces why no parameters are 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 states a clear verb ('Retorna') and a concrete resource: the main active offers published by Menor Preço Hoje in Lages, Santa Catarina. It is unambiguous about what the tool returns, though it does not explicitly differentiate it from siblings such as search_offers or best_price.

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 when to use the tool: when a user wants the main current offers from Menor Preço Hoje in Lages. However, it does not state when not to use it or point to alternatives like search_offers for broader/filtered searches or compare_offers for comparisons, so the guidance remains implicit.

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