Current air quality for a place: PM2.5, PM10, ozone, NO2, SO2, CO and dust, plus the US and European AQI and the US AQI band ('Good', 'Unhealthy'). Takes a place name — no coordinates needed. (Free. This server also sells a paid API — call paid_catalogue for the routes and prices; x402 over USDC on Base, no signup.)
| Name | Required | Description | Default |
|---|---|---|---|
| location | Yes | Place name, e.g. 'Tokyo' |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden of behavioral disclosure. It clearly states this is a read-only data lookup and lists the output contents, but it does not mention potential errors, data staleness, units, or response format. The mention of free and paid API is extra context but not essential for using the 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 core instruction is a single information-dense sentence that lists outputs and input requirements. The parenthetical about the paid API is somewhat off-topic for tool usage, adding a minor distraction, but the description remains reasonably concise and well-structured.
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 one-parameter, read-only lookup with no output schema, the description adequately covers what the tool returns and how to specify the input. It does not describe the output structure, but the tool is simple enough that this is not a critical 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?
Schema coverage is 100% and the schema already explains that 'location' is a place name with an example. The description reinforces this with 'place name — no coordinates needed' but adds little 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 clearly identifies the tool as returning current air quality for a place, and enumerates the specific pollutants and AQI metrics included. It distinguishes itself from sibling tools by focusing on air quality and explicitly noting that it takes a place name rather than coordinates.
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 explicitly says 'Takes a place name — no coordinates needed', which guides the agent to use a simple location string and avoid unnecessary geocoding. It does not explicitly compare with sibling tools, so it falls slightly 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.
Add one secure layer between your agents and this server.
Each tool has a clear, distinct purpose (air quality, country indicators, earthquakes, elevation, geocode, holidays, URL reading, web search, catalogue). The only overlap is that geocode already returns elevation, making the separate elevation tool redundant and potentially confusing.
All tool names follow a consistent lowercase snake_case pattern, mixing noun-based names (earthquakes, elevation) and verb_noun names (read_url, web_search). The style is uniform across the set, so naming is predictable and readable.
Nine tools is a reasonable count for a general-purpose data/web utility server. However, the set feels like a random assortment of free APIs rather than a coherent scoped collection, which slightly undermines the sense of appropriateness.
The server name 'tokenguard' implies a focus on token safety and blockchain intelligence, but the free tools cover unrelated domains (air quality, geocoding, holidays, web). The actual token-safety features are only mentioned in the paid_catalogue and are not exposed as MCP tools, leaving a significant gap between the server's apparent purpose and its actual capabilities.