Companion check

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

Annotations declare readOnlyHint and openWorldHint, but the description adds substantial behavioral detail: the mechanism behind 'bad' (botanical family, pest susceptibility, not folklore) and 'good' (Permapeople listing when configured), plus the return behavior (every matched reason returned, including overridden ones). This goes beyond annotations and provides clear expectations.

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 two sentences, front-loaded with the core purpose and then providing mechanism and return behavior. No redundant words; every clause adds value. Excellent conciseness.

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?

The description explains the purpose, the logic behind verdicts, and what is returned. With no output schema, it sufficiently covers the expected result behavior. It doesn't state the exact return format, but that's not essential for a read-only check with clear semantics. It's nearly complete, missing only minor format specifics.

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?

The schema descriptions cover both parameters clearly: plant_a as a species id or name, plant_b as the plant to check. The description itself adds no extra parameter semantics, but the mention of 'species id from search_plants' in the schema and the overall context is adequate. Baseline 3 is appropriate given 100% schema coverage.

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 clearly states the tool checks whether two plants should share a bed, explaining the criteria for 'bad' and 'good' verdicts. It distinguishes itself from siblings (search_plants, plant_details, planting_window) by focusing on companion compatibility, not search, details, or timing.

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 context implies when to use: to check plant compatibility. The plant_a parameter mentions 'A species id from search_plants', linking to a sibling for finding ids, and the description mentions 'when that source is configured', a prerequisite. However, it doesn't explicitly state when NOT to use it or contrast with alternatives like plant_details.

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