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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, so the safety profile is clear. The description adds valuable behavioral context: it explicitly states case-insensitive substring matching, that it returns ALL matching satellites, and discloses the data source ('US Space Force via CelesTrak') and that no auth is needed. This goes beyond the annotations without contradicting them.

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 succinct (4 sentences) and front-loaded with the core purpose. It wastes no words: the first sentence defines the action, the second the output, the third provides illustrative examples, and the fourth adds provenance and auth context. Every sentence earns its place.

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 single-parameter read-only tool, the description is complete. It covers what the tool does, what it returns (listing fields), typical use cases, data source, and auth requirements. An output schema exists, so return-value details are not required in the description. Nothing an agent needs to call it correctly is missing.

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%, and the schema's parameter description is already rich (explains substring matching, case-insensitivity, examples, minimum length). The tool description mostly repeats these details (examples, return behavior) rather than adding new semantic nuance. Baseline of 3 is appropriate since the schema carries the load.

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 ('Search'), a clear resource ('NORAD satellite catalog'), and the exact matching behavior ('by name substring, case-insensitive'). It also enumerates the returned fields (NORAD catalog number, COSPAR ID, epoch, full orbital element set), making it unambiguous. It distinguishes itself from sibling celestrak tools (group, intdes, tle) by virtue of being name-based.

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 gives concrete use cases ('finding the NORAD IDs and TLEs of satellites by operator or mission name') with representative examples (STARLINK, NOAA, GPS, FENGYUN, ISS). It also notes 'no auth required', which is contextually helpful. However, it does not explicitly contrast with alternative celestrak tools (e.g., when to use intdes or group instead), so it falls short of a full 5.

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