Astronomer MCP Server

create_cosmic_structure

Create a new galaxy or cluster record in the cosmic structure catalog by providing a name and optional astrophysical description.

Instructions

Create a new cosmic structure (galaxy or cluster) record in the catalog.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "name": "<name>"
    },
    "name": "create_cosmic_structure"
  }
}

Input Schema

Name	Required	Description	Default
`name`	Yes	Name of the cosmic structure (e.g. 'Milky Way', 'Andromeda Galaxy M31')
`description`	No	Astrophysical, morphological, and extragalactic description

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Nov 13, 2026

TDQS

C2.9/5.0

Behavior2/5

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

No annotations are supplied, so the description carries the full behavioral burden. It states only that a record is created in the catalog; it says nothing about duplicate-name handling, whether an identifier is returned, required permissions, or whether the write is reversible. For a mutation tool with zero annotation coverage this is a substantial gap.

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?

A single front-loaded sentence with zero wasted words; the parenthetical definition of 'cosmic structure' is placed where it is most useful. Its brevity reflects under-specification rather than poor structure.

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

Completeness2/5

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

For a mutation tool with no annotations and no output schema, the definition does not say what happens on success (returned ID or full record) or on conflicts. An agent can attempt the call but cannot predict its side effects or failure modes from this text.

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 both parameters are already documented in the schema, which sets the baseline at 3. The description adds only the semantic framing that the record represents a galaxy or cluster, with no detail on name uniqueness or description content beyond the schema.

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

Purpose4/5

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

The description uses a specific verb+resource ('Create a new cosmic structure record') and clarifies the domain term with '(galaxy or cluster)'. It does not distinguish itself from adjacent creators such as create_celestial_body or upsert_cosmic_structures_batch, so sibling differentiation is absent.

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

Usage Guidelines2/5

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

There is no guidance on when to use this instead of upsert_cosmic_structures_batch or the other create_* tools, and no stated prerequisites. The agent must infer that this is the single-record creation path.

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

Deploy Server