Bikefuchs — Bike Parts Price Comparison

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is fully covered by structured data. The description adds one genuine behavioral trait beyond that: results are sorted cheapest-first, which tells the agent how to interpret ordering without post-processing. It says nothing about result caps, pagination, or staleness of prices.

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 sentence that front-loads the input (EAN barcode) and then the output contract (shops, prices, availability, sort order). No filler, no restatement of the title or name.

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 an output schema present, the description need not enumerate return fields, and annotations cover the safety profile, so what remains is mostly covered. The one gap is that openWorldHint=false combined with a cross-shop lookup could mislead an agent about where the data comes from, and there is no note on result volume or freshness.

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%, with both ean (pattern, example) and country (enum, default) fully documented in the schema. The description restates the EAN input but adds nothing about the country parameter or its DE/AT pricing effect. Baseline 3 is correct when the schema carries the parameter burden.

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 verb and resource with explicit scope: given an EAN, return every shop carrying it with prices and availability, sorted cheapest-first. This clearly separates it from search_product and resolve_product, which operate on product identity rather than shop listings. It does not explicitly contrast with get_best_price, which is the closest sibling by output, so sibling differentiation is only partial.

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 input precondition (an EAN barcode) is stated, so usage is implied, but there is no when-to-use vs when-not guidance and no mention of the obvious alternative get_best_price for agents that only need the cheapest offer. The agent must infer the routing decision from sibling names 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?

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=false, and destructiveHint=false, covering the safety profile. The description adds sorting, stock status, and purchase links, but an output schema exists so those return details are redundant. No additional behavioral context such as auth or rate limits is provided. Baseline 3 is appropriate.

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, front-loaded sentence that packs purpose, scope, and output shape with zero 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 100% schema coverage, an output schema, and annotations that fully cover safety, the description provides sufficient context. An agent has everything needed to select and invoke the tool correctly.

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 documents all three parameters including the enum for country and the reference_shop comparison behavior. The description does not mention any parameters, so it adds no meaning beyond the schema. Baseline 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?

States a specific verb ('Look up'), resource ('single product by its EAN barcode'), and scope (price at every shop, sorted cheapest-first). It clearly distinguishes from siblings like search_product or resolve_product by requiring an EAN and returning a price comparison.

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 (look up by EAN for price comparison), but does not explicitly say when to use this tool versus alternatives like search_product or resolve_product. No exclusions or alternatives are named.

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 already establish read-only, idempotent, non-destructive behavior, and the description adds no further side-effect or operational context such as costs, errors, or special cases. The mention of tiers and the free-shipping threshold describes output content rather than a behavioral trait, so no significant extra value beyond the safety annotations is added.

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, front-loaded sentence starts with the action ('Return the exact shipping cost') and packs the required parameters and outputs into one efficient clause. There is no filler, repetition, or tangential information.

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 three-parameter read-only tool with a full input schema, complete annotations, and an output schema available, the description supplies all context an agent needs to decide and invoke correctly. It explains the key derived output, the free-shipping threshold gap, that a caller would otherwise not anticipate.

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% with detailed descriptions for all three parameters, so the schema carries the meaning. The description restates the parameter concepts but adds no new format, unit, or edge-case information beyond 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?

The description names a precise action (return exact shipping cost), a clear resource (a specific shop, country, and cart value), and the distinct outputs (all shipping tiers and the gap to free-shipping). This differentiates it from sibling tools such as get_best_price, which concern product pricing rather than shipping cost.

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?

It clearly implies when to use the tool: whenever the agent needs the shipping cost for a known shop, country, and cart value. It doesn't explicitly list alternatives or exclusion conditions, but the strong context makes the intended use obvious.

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 already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is well covered. The description adds content-level context but no additional behavioral traits such as rate limits, required permissions, or data-source caveats. This is acceptable given the strong annotation coverage.

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 front-loaded sentence with no filler or redundant information. Every clause adds value: the resource, the nature of the output, and the specific countries covered are all stated efficiently.

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?

This is a simple read-only tool with one optional parameter, a rich schema, an output schema, and strong annotations. The description provides enough detail about the returned content and the supported countries for an agent to invoke it correctly without further clarification.

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%, with the schema already documenting the optional country parameter and its DE/AT restriction. The tool description reinforces that DE and AT are the supported countries but does not add new meaning beyond the schema, 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 states a specific verb and resource ('Return an overview of the supported shops') and enumerates concrete contents: shipping cost tiers, free-shipping thresholds, and countries DE/AT. This clearly differentiates it from siblings like get_shipping_breakdown or get_best_price, which focus on transactional or pricing details rather than shop-level overviews.

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 says what the tool returns but gives no guidance on when to prefer it over alternatives or when not to use it. It does not mention any sibling tools or conditions that would route an agent to get_shipping_breakdown, get_best_price, or optimize_cart instead.

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 already declare readOnlyHint, idempotentHint, and openWorldHint=false, so the safety profile is covered. The description adds real behavioral context: it accounts for shipping costs and free-shipping thresholds and guarantees the lowest achievable total including shipping, which is more than the annotations convey.

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 front-loaded with the core behavior, then the input, then the prerequisite workflow. It stays efficient, though the first sentence's clauses are dense enough that the 'what it returns' point could be sharper.

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?

An output schema exists, so return values don't need explaining, and the description supplies the key workflow context that would otherwise be missing. It doesn't mention that only DE/AT are supported or the 20-EAN cap, but the schema covers both.

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%, so both the eans array and the country enum are fully documented in the schema. The description only repeats that it takes an array of EAN barcodes and says nothing extra about country or the 20-item cap, so baseline 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 states a specific verb and resource — it computes the cheapest way to split a multi-item purchase across shops and returns the lowest total including shipping. It clearly distinguishes itself from siblings like get_best_price (single-item pricing) and get_shipping_breakdown (per-shop cost detail).

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?

It gives an explicit prerequisite: call get_best_price for each EAN first, then call optimize_cart. That sequencing guidance is concrete, though it doesn't say when *not* to use this tool or how it relates to get_shipping_breakdown for a detailed breakdown.

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 already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds genuinely new behavior beyond that: multi-variant families return a labeled candidate list rather than a single product, and the agent must ask the user to pick before proceeding. It does not mention failure modes for unsupported shops or ambiguous URLs.

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 tightly packed sentences with the core capability front-loaded and the variant-handling caveat second. Dense but every clause carries information; no filler or repetition of the title.

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?

An output schema exists, so return values need not be re-explained, and annotations cover the safety profile. The description supplies the one non-obvious piece an agent needs — the multi-variant candidate-list flow and the required user confirmation step — which would otherwise cause incorrect downstream EAN usage.

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 both parameters (url, country) are documented in the schema with format and enum. The description only loosely restates 'URL from a supported shop' and says nothing about the country parameter, so it adds little beyond the schema. Baseline 3 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?

States a specific verb+resource ('Turn a product page URL ... into structured product data') and enumerates the outputs (EAN, price, stock status, purchase link). It also positions itself against siblings by naming get_best_price and optimize_cart as the downstream consumers of the EAN.

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?

Clearly frames when to use it (you have a product URL and need an EAN) and names the downstream alternatives to hand off to. It also gives a concrete branching instruction for multi-variant families. It stops short of stating a when-not case, e.g. that an already-known EAN should skip this tool.

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 already cover read-only, idempotent, non-destructive, and closed-world behavior. The description adds useful behavioral detail: results are sorted cheapest-first and pricing supports DE and AT. It does not disclose rate limits or default stock filtering, but those are either schema-covered or minor.

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 front-loaded and mostly efficient, with the alternative tool named at the end. The sentence listing returned fields is slightly redundant because an output schema exists, though the cheapest-first sorting detail still 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?

Given annotations, full schema coverage, and an output schema, the description provides enough context to call the tool correctly: it covers purpose, result ordering, country support, and the key alternative sibling. Nothing essential is missing for an agent deciding whether to invoke it.

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%, so the schema already explains all seven parameters in detail. The description adds only modest meaning, mainly that the query may target a brand or model number and that pricing supports DE/AT; it does not add syntax or filtering semantics beyond 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?

It states a specific verb and resource: searching bicycle products by name, brand, or model number across clearly named categories. It also distinguishes itself from the closest pricing sibling by telling the agent to use get_best_price when an EAN is already known.

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 says when to use it (searching parts/components/accessories/clothing by name, brand, or model number) and names the explicit alternative when an EAN is already available. This is a clear routing rule, not just implied guidance.

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