tess_known

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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so safety profile is covered. The description adds genuine value by naming the upstream catalogs and explaining the TIC-only fallback to TIC v8.2 positions. It does not explain the angular search behavior implied by radius_arcsec or what happens when both TIC and coordinates are supplied.

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?

Two tight sentences that front-load the returned content and follow with the input/catalog caveat. No filler, though the dangling catalog citations could be folded more economically.

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-value explanation is not required, and the input modes and data sources are covered. The gap is the undocumented search-radius parameter, which materially affects results for a cone-search tool.

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% across four parameters, so the description must compensate and largely does not. It implies tic and ra/dec are alternative input modes but never documents units, frame, or the 30-arcsec default search radius of radius_arcsec — the parameter most likely to be misused.

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 (TOIs/CTOIs from ExoFOP-TESS and TESS eclipsing binaries from Prsa et al. 2022) retrievable by TIC id and/or sky position. An agent can tell this returns known-object catalog matches rather than raw photometry or ephemerides. It does not, however, differentiate itself from conceptually overlapping siblings like whats_here or simbad.

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 says what inputs are accepted but never states when to prefer this over whats_here, simbad, or vsx, nor any exclusions or prerequisites. The only conditional statement ('with only a TIC, its position comes from TIC v8.2') is a data-provenance note, not usage routing.

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