tap_expand_tools

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

The description fully discloses the behavioral impact: after calling, the server sends notifications/tools/list_changed, and clients that honor it will re-query tools/list automatically. This explains the dynamic nature of the tool set expansion. The annotation 'openWorldHint: true' aligns with the description, confirming that the tool can change available tools. There is no contradiction.

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 a single paragraph that is generally concise and front-loaded with the main action. Every sentence adds value, but it could be slightly more streamlined. For example, the list of level-3 tools is helpful but somewhat lengthy. Overall, it is well-structured and informative without being verbose.

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 tool with only one parameter, no output schema, and complex behavior (expanding the tool set with side effects), the description covers all essential aspects: purpose, when to use, level details, server notification, and client behavior. It is complete enough for an agent to decide correctly whether and how to invoke this tool.

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?

Although the schema provides an enum for the 'level' parameter with values 2 and 3, the description adds significant meaning by explaining that level 2 is 'creative (forge supplements + diagnostics)' and level 3 is 'manual (raw browser control: tap.click, tap.type, etc.)'. It also clarifies that higher-level calls subsume lower ones, which is not evident from the schema alone. With 100% schema coverage, the description goes beyond the baseline 3.

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 tool's purpose: to expand the MCP tool set. It specifies the context when the default Layer-1 set is insufficient, and explicitly lists the types of operations (e.g., browser actions, write-tap operations, diagnostics) that warrant its use. This distinguishes it from sibling tools like 'tap_run' or 'inspect' by focusing on tool set expansion rather than individual tool execution.

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 description provides explicit guidance on when to use the tool ('when default Layer-1 set is insufficient') and gives concrete examples of needed actions. It explains the two levels (2 and 3) and what each exposes, including the condition that higher levels subsume lower ones. The description also notes the side effect of server notification and client re-query, which helps agents understand the invocation context.

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