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Glama

find_hydrogen_station

Read-onlyIdempotent

Returns hydrogen (H2) filling stations near a place or coordinate, nearest first, with operator, address, pumps (700 bar car, 350 bar truck/bus), opening hours where published and the age of the record.

Instructions

Returns hydrogen (H2) filling stations near a place or coordinate, nearest first, with operator, address, pumps (700 bar car, 350 bar truck/bus), opening hours where published and the age of the record. Use when someone asks where to refuel a fuel-cell car, lorry or bus ("Wasserstofftankstelle", "H2 tanken", "hydrogen station near me"). Do NOT use for petrol or diesel (call find_fuel_station) or EV charging (call find_charging_station); LPG/Autogas and CNG are not held — say so. Radius ≤ 150 km, ≤ 10 stations; no live availability or price is published. Shows the attribution line.

Input Schema

NameRequiredDescriptionDefault
latNoLatitude in WGS 84, e.g. 48.137. Use with lon when the caller already holds coordinates; otherwise use place.
lonNoLongitude in WGS 84, e.g. 11.576. Use with lat; otherwise use place.
limitNoHow many stations to list, nearest first (1–10, default 5).
placeNoWhere to look, as free text: a city ("München", "Munich"), a district or Kreis ("Kreis Fulda"), a Bundesland, a station or stop ("Hamburg Hbf"), a motorway junction ("AK Neufahrn"), or a street address with a house number ("Bahnhofstraße 12, 36037 Fulda"). A motorway number alone ("A7") resolves to the road, which has no single point — name a town or junction on it instead. Use this instead of coordinates whenever the person named a place. An address needs its town or postcode — a street and a number alone exist in many towns. Give either place OR lat+lon, never both.
vehicleNoWhich pump the vehicle needs: "car" (Pkw — 700 bar, e.g. Toyota Mirai, Hyundai Nexo; a few sites also offer 350 bar for cars) or "truck" (Lkw or bus — 350 bar). Omit unless the person said what they drive.
languageNoSet this on every call to the language the person is writing in: "en" if they wrote English, "de" if they wrote German. Do not leave it out: it defaults to German ("de"), which is only the fallback when the language is genuinely unclear, so an English question sent without it is answered in German — a wrong answer. Place names, station names and road numbers are never translated in either language; in English the German term is kept in parentheses so the person recognises it on signs and in local apps.de
radius_kmNoSearch radius around place or lat+lon in kilometres (1–150, default 50). Hydrogen stations are few, so the default is wide; when none is inside, the answer still names the nearest one beyond. Example: 50

Schema Changelog

Changes observed during successful MCP inspections.

  1. Addedv2.1.18

TDQS

A4.6/5.0
Behavior5/5

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

Annotations already declare readOnly/ idempotent/ non-destructive, and the description adds genuinely new behavioral context: hard limits (radius ≤150 km, ≤10 stations), the absence of live availability or price data, the 'nearest one beyond radius' fallback, and the attribution line requirement. This is disclosure beyond what structured fields provide.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with purpose and constraints, then usage and exclusions. The German/English trigger phrases and the exhaustiveness of the exclusion list make it longer than strictly minimal, but every sentence is decision-relevant rather than filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description compensates by enumerating returned fields (operator, address, pump pressures, hours, record age) plus the attribution line. Combined with alternatives, limits, and language handling, an agent has everything needed to select and call it correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents lat/lon/place/vehicle/language/radius/limit thoroughly. The description only echoes a couple of limits (radius ≤150 km, ≤10 stations) that the schema already states, so it adds little new parameter meaning. Baseline 3 is appropriate when the schema carries the load.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Returns hydrogen (H2) filling stations near a place or coordinate, nearest first') and lists what each result carries (operator, address, pumps, hours, record age). It explicitly names the sibling tools it is not (find_fuel_station, find_charging_station), so an agent can distinguish it without opening other schemas.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives explicit positive triggers ('where to refuel a fuel-cell car, lorry or bus') and explicit exclusions with the correct alternatives for petrol/diesel and EV charging. It also flags that LPG/CNG are not held at all, closing an otherwise likely misuse path.

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