list_engines

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

Annotations already declare readOnlyHint=true, so the '[READ]' prefix adds nothing beyond structured data. The description does add useful behavioral context via the 'SHOW ENGINES' mapping, telling the agent what backend call is made and what information comes back (engines + default), but it says nothing about permissions, connection requirements, or result shape.

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?

Front-loaded with the purpose and backend mapping, followed by a single compact arg note — no filler sentences. The '[READ]' tag is slightly redundant given the annotation, but overall it is tight and appropriately sized for a one-parameter read tool.

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 read-only, zero-required-parameter tool with no output schema, the description covers what the tool returns (engines and the default), the optional argument, and its default behavior. Nothing essential to correct invocation is missing; only edge details like error behavior under an unknown target are absent.

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%, so the description has to carry the parameter burden, and it largely does: it names 'target', explains it comes from config, and states that omitting it falls back to the default. That is real semantic value beyond the bare `anyOf string|null` schema, though it doesn't say what a target name looks like or how to discover valid values.

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 verb+resource ('Storage engines') plus the discriminating detail 'which is the default', and maps to the underlying command (SHOW ENGINES). No sibling covers engines, so sibling differentiation isn't needed. It stops short of 5 only because the phrasing is terse and could be read as a label rather than a full statement of intent.

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 — an agent calls this to enumerate storage engines — and the only explicit guidance ('omit for the default') concerns the target parameter rather than when to choose this tool. There is no competing sibling to exclude, so the missing when/when-not framing is a modest gap rather than a serious one.

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