get_stage_profiling

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

With no annotations, the description carries the burden and discloses a genuinely non-obvious behavioral constraint: the instance must be built with the `profiling` feature, otherwise the call presumably fails. It also characterizes the payload (wall-clock timing per callback stage plus the slowest stage). It does not say what happens with no matching records or when the feature is absent, keeping it short of a 5.

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 sentences, front-loaded with the core action and return value, with the prerequisite placed last. The heavy parenthetical is dense but every clause adds information; no filler.

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?

No output schema exists, so the description must cover return content — and it does, naming per-stage wall-clock timings and the slowest stage. The feature-gate prerequisite is a key operational detail. It is close to complete, lacking only failure/empty-result behavior.

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%, so both `endpoint` (fallback to AIMDB_CONNECT) and `record_key` (substring match with example) are fully documented in the schema. The description adds no format or matching semantics beyond what the schema provides, so the baseline 3 applies.

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 ('Get') and resource ('automatic stage profiling') with precise scope: per-`.source()`/`.tap()`/`.link()` callback wall-clock timing for records matching a key. The phrase 'from a running AimDB instance' and the returned 'bottleneck' value make it clearly distinguishable from siblings like reset_stage_profiling or get_buffer_metrics.

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?

Provides a real precondition ('Requires the instance to be built with the `profiling` feature') and scopes usage to a running instance, which is useful context. However, it never says when to choose this over alternatives such as get_buffer_metrics or how it relates to the reset_stage_profiling sibling, so usage selection is only implied.

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