Fetch NASA's Astronomy Picture of the Day for today or a chosen date, including the image and explanation, using a NASA API key.
今日（または指定日）の NASA の今日の天文写真(APOD)を返す。NASA_API_KEY が必要。
| Name | Required | Description | Default |
|---|---|---|---|
| date | No |
Changes observed during successful MCP inspections.
v0.41.4Input schema / properties / date / anyOfRemoved value: -[
- {
- "type": "string"
- },
- {
- "type": "null"
- }
-]Input schema / properties / date / defaultRemoved value: -nullInput schema / properties / date / titleRemoved value: -"Date"Input schema / properties / date / typeAdded value: +[
+ "string",
+ "null"
+]Input schema / titleRemoved value: -"_nasa_apodArguments"v0.25.2Output schema / (root)Previous value: -{
- "properties": {
- "result": {
- "title": "Result",
- "type": "string"
- }
- },
- "required": [
- "result"
- ],
- "title": "_nasa_apodOutput",
- "type": "object"
-}New value: +nullv0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description must carry behavioral context. It usefully discloses that a NASA_API_KEY is required, but it does not describe rate limits, error behavior, caching, or return characteristics.
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 short and front-loaded, stating the return value first and the API-key requirement second. There is little wasted text, though the key requirement could be integrated more tightly.
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 simple one-parameter fetch tool with no output schema, the description covers the core purpose and authentication requirement. It remains incomplete about the date parameter format and expected return shape.
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 0%, so the description should clarify the single date parameter. It merely says the date can be specified and does not provide format, accepted range, timezone, or what null/omitted means beyond implying today.
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: returns NASA's Astronomy Picture of the Day for today or a specified date. It is clear what the tool does, though it does not explicitly distinguish itself from image-search siblings such as search_space_images.
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 indicates the tool can return today's APOD or a specified date's APOD, which implies the basic use case. However, it gives no guidance on when to use this instead of sibling image or astronomy tools, and 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.