constants

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

Annotations declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds real behavioral context beyond that: this tool cannot change anything, and edits require owner approval plus a journal entry, which warns the agent off treating it as a config mutator.

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, no filler, with the return-shape enumeration front-loaded and the change-workflow caveat following. Every clause carries information.

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 zero-param read tool with no output schema, the description enumerates the returned fields and states the mutation path, which is enough to call it correctly. Minor gaps remain about volume or grouping, but nothing essential is missing.

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?

Zero parameters, so the baseline of 4 applies. The description usefully clarifies that the returned records include unit and kind taxonomies (measured/research/rule/heuristic), which shapes how the agent interprets output.

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 resource (engine constants) and enumerates exactly what each entry carries: value, default, unit, kind, and source. An agent can tell this is the read-only constants registry and not one of the many data/analysis siblings.

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 second sentence redirects mutation away from this tool: changing values happens in config/constants.toml under owner approval with a journaled rationale. It gives clear context for read vs. change, though it doesn't explicitly name a sibling tool to use instead.

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