get_capabilities

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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so safety behavior is covered. The description adds that the response inventory includes session/cache state and saved history, which is mild extra context, but it says nothing beyond that about what reading this state does or how fresh it is.

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?

It is two tight fragments with the contents front-loaded and the usage cue at the end; nothing is padded. The list-style phrasing is slightly ambiguous about whether these are returned or configured, which keeps it from a 5.

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?

With an output schema present, return-shape detail is unnecessary, and annotations cover the safety profile. For a simple, parameter-free discovery tool the description is nearly complete, lacking only an explicit 'first call in a session' framing.

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 tool takes no parameters, so the schema carries no semantic burden and the baseline for zero-param tools applies. Nothing in the description is needed to compensate for parameter documentation.

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 enumerates what the tool surfaces (version, settings, session/cache state, saved history, tool list), which is specific for a zero-param introspection call, but it uses a bare noun list with no verb and no differentiation from siblings like check_endpoints or clear_cache. An agent can infer it is a discovery/state tool, but the phrasing leaves the action implicit.

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?

'Call this first when unsure' gives an explicit, actionable trigger for invocation. It stops short of naming when-not-to-use conditions or alternative siblings, so it is clear context rather than full routing guidance.

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