rubin_object

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

Annotations already declare readOnly, idempotent, and open-world access, so safety is covered. The description adds real behavioral detail beyond that: it returns data from the latest alert only, magnitudes are converted to AB from nJy flux, and cutouts are provided as links rather than pixels. It does not say what happens for an unknown ID, but that is a minor omission.

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 sentence that front-loads the resource and key, then lists the three return elements in order of importance. No filler, no restatement of the tool name.

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?

An output schema exists, so return values need not be explained, yet the description still previews the payload shape, which helps an agent decide if this tool has what it needs. Combined with annotations covering read-only/idempotent behavior, the only gap is error/miss handling, which is minor for a one-parameter lookup.

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% for the single required parameter, dia_object_id, which has no format, example, or type guidance in the schema. The description names the concept ('by diaObjectId') and thereby ties the parameter to the Fink broker namespace, but supplies no syntax or source for obtaining an ID, so it only partially compensates.

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 resource (Rubin/LSST object from the Fink broker) and the exact retrieval key (diaObjectId), and enumerates what comes back: position, light curve, cutout links. That scope implicitly separates it from rubin_recent (a listing tool) and ztf_lightcurve, though no sibling is named explicitly, keeping it 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?

Usage is implied rather than stated: 'by diaObjectId' signals this is the single-object lookup, opposite rubin_recent's recency-based query. There is no explicit when-to-use, no instruction on where to obtain a diaObjectId, and no stated alternative for users who only have coordinates (a different tool, presumably).

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