Open a .geo.json model

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

Annotations only declare non-read-only, non-destructive, non-idempotent, closed-world; the description adds real behavior: a new tab is created, format conversion happens when the GeckoLib plugin is installed, and an already-open file switches to its tab instead of duplicating. It does not cover failure modes for missing/invalid files, which is the main remaining gap.

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 verb and resource, then the optional sidecars, then the dedup behavior. No redundant restatement of the title or schema.

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 open-file tool with full schema coverage and no output schema, the description covers format handling, sidecar attachments, conversion, and tab reuse. Only edge-case behavior (missing file, invalid JSON) is unstated, a minor gap at this complexity.

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 all five parameters (paths, reload, reopen) are already documented in structured form. The description adds only loose correspondence ('optionally with its .animation.json and texture PNG') and no new semantics for reload/reopen or path prefixes, so 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 ('Opens') and a precise resource (an existing Bedrock/GeckoLib .geo.json), plus the result (a new tab). The qualifier 'Bedrock/GeckoLib .geo.json' implicitly separates it from the sibling open_java_model, so an agent can pick correctly without opening schemas.

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?

Clear context for use: open an existing model file, optionally attaching its .animation.json and texture PNG, with tab-dedup behavior described. It stops short of explicitly excluding alternatives (e.g., open_java_model for Java-format models, new_project for fresh projects), leaving that routing to inference from the file format.

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