list_phyla

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

No annotations are provided, so the description carries the full burden. 'List' plus the read-only nature of taxonomy browsing makes the safety profile reasonably clear, but it says nothing about ordering, result volume, or what the entries look like when returned.

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 with the core action front-loaded and the positional hint second. Nothing is padded or redundant.

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 simple, fully documented, read-only listing tool with no output schema, the definition covers what an agent needs: what it returns conceptually and that it operates at the root of the taxonomy. A note on how the returned phyla feed into other tools would make it fully complete.

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 single domain parameter has an enum plus an 'If omitted, lists all phyla' note, so the schema already does the work. The description only echoes the Bacteria/Archaea choice without adding format or behavior detail beyond it.

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 gives a specific verb and resource ('List all bacterial or archaeal phyla in GTDB') and states its position as the top-level entry point, which helps separate it from get_children and list_taxa_by_rank. It is clear, though it does not explicitly name the sibling tools that cover other ranks.

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?

'This is the starting point for exploring the taxonomy tree from the top level' implies when to reach for it, but no alternatives or exclusions are named (e.g. when to prefer list_taxa_by_rank or get_children for deeper levels). Usage is inferable but not spelled out.

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