add_symbol

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

No annotations are present, so the description carries the full burden. It only states that a symbol is added, which is a mutation, but it does not disclose side effects, prerequisites (e.g., diagram must exist, element must exist), reversibility, or error conditions. The 'Phase B stub' hint suggests incompleteness but does not explain expected behavior or limitations.

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?

The description is extremely short, but this is under-specification rather than conciseness. It lacks any structure or emphasis on key information. The 'Phase B stub' is tacked on without explanation. There is no front-loading of important constraints or usage context. A concise description would still convey essential details in a few sentences; this one conveys almost nothing.

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?

Given the tool's complexity (two required parameters, many sibling tools), the description is incomplete. It does not explain what an element symbol is, how it relates to diagrams, or what the output schema contains. Since an output schema exists, the return value may be documented there, but the description still fails to provide necessary context for an agent to decide whether this tool is appropriate and what to expect. The 'Phase B stub' further signals incompleteness.

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%, and the description does not mention either parameter. It only says 'add an element symbol to a diagram' without explaining what diagram_id and element_id represent. The description adds no meaning beyond the parameter names in the schema, leaving the agent to infer that diagram_id identifies the target diagram and element_id identifies the element whose symbol is added. This is insufficient.

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 clearly states the action: adding an element symbol to a diagram. It uses a specific verb and resource, and it distinguishes from siblings like remove_symbol, move_symbol, and resize_symbol. However, it does not elaborate on what an element symbol is or how it differs from creating an element (e.g., create_block), and the 'Phase B stub' qualifier introduces ambiguity about its current functionality.

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 guidance on when to use this tool versus alternatives. It does not mention that it is for adding symbols to diagrams rather than creating elements, nor does it reference any sibling tools. The 'Phase B stub' note implies it may not be ready for production use, but this is not framed as usage guidance. No when-to-use or when-not-to-use conditions are provided.

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