Get map tile

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

With no annotations provided, the description carries the full burden. It discloses the return format (PNG tile plus metadata and attribution) and the API key requirement for certain styles, which is valuable contextual behavior beyond the schema. It does not mention rate limits or error scenarios, but the key disclosures are present.

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 concise and efficiently front-loaded: it starts with the core purpose, then lists styles and key requirements, and ends with the output. Every sentence adds value, with no redundant repetition of schema details.

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 the tool's moderate complexity, no output schema, and no annotations, the description covers the essential aspects: purpose, parameter semantics for style, authentication requirements, and return type. It lacks explicit error handling or prerequisites beyond the API key, but is otherwise complete for selecting and invoking 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?

The schema already covers all parameters with 100% description coverage, giving a baseline of 3. The tool description adds extra meaning to the style enum by explaining each style's source and whether a key is needed, which goes beyond the schema's simple description of 'Map style / layer to render'.

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 fetches a rendered map tile as an image, using specific verb 'Fetch' and resource 'map tile'. It is distinct from sibling tools that focus on places, geocoding, or routes, and explicitly mentions the map layer viewing purpose.

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 provides clear context for when to use the tool (view a map layer as an image) and gives style-specific guidance (which styles require the Thunderforest API key). It does not explicitly exclude alternative tools or name alternatives, but the context is sufficient for an agent to differentiate from spatial data tools.

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