Queries NASA Exoplanet Archive for confirmed exoplanet data by planet or host star name, returning up to a set number of results.
Query NASA Exoplanet Archive for confirmed exoplanet data
| Name | Required | Description | Default |
|---|---|---|---|
| lang | No | Output language | en |
| hostname | No | Host star name (e.g. "TRAPPIST-1", "Kepler-22") | |
| max_results | No | Maximum number of results | |
| planet_name | No | Planet name (e.g. "Kepler-22 b", "TRAPPIST-1 e") |
Changes observed during successful MCP inspections.
v2.1.2Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden. It implies a read-only query but says nothing about pagination/limits, output format, the fact that all four parameters are optional, or what is returned when no filter is supplied. For a query tool with zero annotation coverage this is a meaningful gap.
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?
A single front-loaded sentence with no filler; the resource is stated immediately. It is efficient, though arguably too terse for a tool whose behavior (optional filters, defaults) needs some framing.
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 4-parameter query tool with no output schema and no annotations, the description is minimally adequate: it identifies the source and data type. It omits what happens with unfiltered queries, the default result cap behavior, and any hint at return structure, which an agent would want before calling it.
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 100%, so each parameter (lang, hostname, max_results, planet_name) is already documented with examples and defaults. The description adds nothing parameter-specific, which is acceptable given the schema does the work, so the baseline 3 applies.
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 (Query) and a specific resource (NASA Exoplanet Archive for confirmed exoplanet data), and the named data source distinguishes it functionally from sibling services like simbad_query, vizier_query, and gaia_adql. It does not explicitly say how it differs from those siblings in scope or filtering, so it stops short of a 5.
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?
There is no when-to-use guidance, no alternative tools named for related tasks (e.g., host-star lookups via simbad_query), and no statement of prerequisites. The only signal is the implied 'use this for exoplanet data' from the name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.