register_crs_definition

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

With no annotations, the description carries the full behavioral burden. It discloses that the registration makes the CRS available to future reprojection tools, indicating a global side effect, and identifies the required proj4 backing. It omits important behavior such as whether re-registering an existing code overwrites or errors, persistence scope, and failure conditions for invalid proj4 strings.

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 with no wasted words. The purpose is front-loaded, followed immediately by the two parameter clarifications, making the description easy to parse at a glance.

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 two-parameter registration tool with no output schema, the description covers the essential call semantics. However, it omits duplicate-code behavior and what happens on invalid input, which are relevant for correct invocation and error handling.

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 must supply parameter meaning, and it does: 'code' is shown by example as 'EPSG:4548', and 'definition' is identified as a proj4 string. This meaningfully compensates for the bare schema, though it does not enumerate accepted code patterns or proj4 syntax validation details.

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 states a specific verb+resource: register an EPSG-style CRS definition with proj4. It also clarifies the intended downstream effect ('so future reprojection tools can use it'), which helps distinguish it from reprojection/transform siblings. It does not explicitly name or differentiate against nearby siblings like set_project_crs or list_known_crs.

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 phrase 'so future reprojection tools can use it' implies this tool should be used before reprojection workflows that depend on a custom CRS. However, there is no explicit when-to-use, when-not-to-use, or named alternative guidance for choosing between this and set_project_crs, list_known_crs, or transform/reprojection tools.

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