Add Instruction

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

Annotations already declare this is a non-read-only, non-destructive, non-idempotent local mutation, so the safety profile is covered. The description adds nothing beyond that: it does not say the schematic file is modified, that repeated calls append duplicates (relevant given idempotentHint=false), or where the addition lands.

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?

A single short, front-loaded sentence with no filler. It is concise, but the brevity is under-specification rather than efficiency, so it only meets the minimum bar.

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 5-parameter mutation tool with 20% schema coverage and no output schema, the description is far too thin. An agent lacks the information needed to know what gets modified, how x/y are used, or what happens on repeat calls.

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 only 20% (only workspace_root is documented), so the description is expected to compensate and largely fails. It weakly implies 'text' holds the directive/comment content, but says nothing about schematic_path, x, or y (placement), leaving four parameters undocumented in both places.

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 verb ('Add') and two resource types ('SPICE directive or a comment'), so the basic action is legible. However, it never defines what an 'instruction' is or how directive-vs-comment differs, and it does not distinguish itself from close siblings like add_net_label, add_wire, or remove_instruction.

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?

There is no when-to-use guidance, no mention of prerequisites (e.g. an open/valid schematic), and no routing to alternatives such as remove_instruction or the other add_* tools. The agent must infer all of this from the name alone.

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