Search ~97,000 used vehicles in the Netherlands with consumer finance and lease monthly payments.
Scored across 2 tools
The two tools have clearly distinct roles: one retrieves valid taxonomy filter values, the other performs the vehicle search. Their descriptions explicitly position list_filter_values as a prerequisite helper for search_vehicles, so an agent should not confuse them.
Both names use consistent snake_case with a verb-first pattern: list_filter_values and search_vehicles. The convention is predictable despite the compound noun in list_filter_values.
Two tools is slightly below the typical 3-15 range, but both are well-scoped and earn their place for a focused vehicle search server. The surface is minimal rather than bloated.
The set covers the core search workflow well, including a taxonomy helper to avoid silently ignored filters. A dedicated vehicle-detail or pagination-oriented tool is not present, but agents can likely work through search results.
Returns all valid filter values (makes, models, colors, fuel types, etc.) from the official taxonomy. Use this before searching if you are not sure which code a make or model has — the API silently ignores invalid values.
| Name | Required | Description | Default |
|---|---|---|---|
No parameters | |||
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No hint annotations exist beyond a title, so the description carries the behavioral burden — and it delivers the single most important trait: invalid values are silently ignored by the API, which motivates the lookup. It stops short of describing response shape or size of the taxonomy payload.
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: one defines the return set, the second gives the usage trigger and the consequence of skipping it. Front-loaded, no filler, and the caveat about silent failures is worth its length.
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 zero-parameter read tool with no annotations and no output schema, the description covers purpose, content domains, and invocation timing. A brief note on the response structure (e.g., grouped by filter type) would close the last gap.
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 tool takes zero parameters and the schema is empty, so there is nothing to document; the baseline of 4 applies. The description correctly implies retrieval of the full taxonomy with no filtering input.
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 ("Returns all valid filter values") and enumerates the taxonomy domains covered (makes, models, colors, fuel types). This is clearly a taxonomy-lookup tool, distinguishable from the search_vehicles sibling without opening any schema.
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?
Explicitly states the trigger condition: "Use this before searching if you are not sure which code a make or model has." That is actionable context, though it does not name search_vehicles as the alternative nor describe the inverse case (when you already know the code, skip this).
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Search used vehicles in the De Autofinancier inventory. All filters are optional and freely combinable. Filter values are lowercase English codes; unknown values are silently ignored by the API (you will then get EVERYTHING back). Use list_filter_values first if you are not sure which codes to use.
| Name | Required | Description | Default |
|---|---|---|---|
| make | No | Merk, kleine letters, bijv. "kia". Meerdere met komma: "audi,bmw". | |
| page | No | Paginanummer, vanaf 1. | |
| sort | No | Sortering: relevance, price-asc, price-desc, monthly-payment-asc, monthly-payment-desc, year-asc, year-desc, odometer-asc, odometer-desc, listed-asc, listed-desc. | |
| color | No | Kleur: black, blue, brown, gray, white, beige, yellow, green, red, silver, creme, gold, orange, pink, purple, other. | |
| model | No | Model, kleine letters, bijv. "niro". Let op: de elektrische Niro heet "e-niro" (tot 2023) en "niro" (2023+, Niro EV). | |
| yearMax | No | Maximaal bouwjaar, bijv. 2026. | |
| yearMin | No | Minimaal bouwjaar, bijv. 2020. | |
| bodyType | No | Carrosserie: suv, stationwagon, mpv, compact, sedan, van, coupe, convertible, pickup, transporter, camper, other. | |
| fuelType | No | Brandstof: electricity (volledig elektrisch), hybrid, petrol, diesel, hydrogen, cng, lpg, e85, hcng, bioethanol, lpgg3, other. | |
| pageSize | No | Resultaten per pagina: 10, 25, 50 of 100. | |
| priceMax | No | Maximumprijs in euro's. | |
| priceMin | No | Minimumprijs in euro's. | |
| odometerMax | No | Maximale kilometerstand, bijv. 60000. | |
| odometerMin | No | Minimale kilometerstand. | |
| transmission | No | Transmissie: automatic, manual, semiautomatic, cvt. | |
| financeProduct | No | Financieringsvorm: consumer-finance of financial-lease. | |
| vehicleCategory | No | Voertuigcategorie: car, van, motor, microcar, camper, caravan. | |
| monthlyPaymentMax | No | Maximale maandlast in euro's. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No functional annotations beyond a title, so the description carries the burden and does deliver a high-value behavioral warning the schema never states: unknown filter values are silently ignored and the agent will get EVERYTHING back, a silent over-broad-result failure mode. It does not disclose pagination limits, total counts, or what the response payload looks like.
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?
Four short sentences, front-loaded with the resource and scope, then the combinability rule, then the silent-ignore hazard, then the recovery path. Every sentence changes agent behavior; nothing is 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 an 18-parameter, fully-optional search with no output schema and no annotations, the description covers the main failure mode and the sibling lookup path. The remaining gap is the result envelope: with no output schema, an agent still does not know whether totals, facets, or pagination metadata come back, or what pageSize interacts with.
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 the baseline would be 3, but the description adds cross-cutting parameter knowledge the schema lacks: filter values are lowercase English codes and invalid codes fail silently rather than erroring. That directly changes how an agent validates and constructs any of the 18 filter params.
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 ("Search used vehicles in the De Autofinancier inventory"), naming the exact inventory domain. It also names the sibling tool list_filter_values as the supporting lookup, so an agent can place it relative to its only sibling without opening any schema.
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?
Gives clear operating context: all filters optional and freely combinable, and an explicit directive to call list_filter_values first when codes are uncertain. It stops short of stating when-not to use this tool (e.g. retrieving a single vehicle by id or listing all inventory with no pagination), so it is strong but not exhaustive.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
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