trace-mcp

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

No annotations are provided, so the description carries full burden. It describes what information is returned but doesn't disclose behavioral traits like whether this is a read-only operation, if it requires specific permissions, whether it's cached or real-time, or what happens if no session exists. The description is purely informational about output content without behavioral context.

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 concise and front-loaded: a single sentence that immediately states the purpose and enumerates the specific metrics returned. Every word earns its place with zero redundancy or unnecessary elaboration. The structure efficiently communicates the tool's function in minimal space.

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 zero parameters and no output schema, the description provides adequate information about what metrics are returned. However, for a tool with no annotations and no output schema, it should ideally clarify the format of the returned data (e.g., structured object vs. text report) and any behavioral constraints. The description is complete enough for basic understanding but lacks depth for optimal agent usage.

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?

With 0 parameters and 100% schema description coverage, the baseline is 4. The description appropriately doesn't waste space explaining parameters that don't exist, though it could have explicitly stated 'no parameters required' for clarity. The description focuses on what the tool returns rather than unnecessary parameter explanations.

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 what the tool does: 'Token savings stats for this session' with specific metrics listed (per-tool call counts, estimated token savings, reduction percentage, dedup savings). It uses a specific verb ('get') and resource ('session stats'), though it doesn't explicitly distinguish from sibling tools like get_session_analytics or get_session_journal.

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 no guidance on when to use this tool versus alternatives. While it mentions 'this session,' it doesn't clarify what constitutes a session, whether this is for current/active sessions only, or how it differs from similar tools like get_session_analytics or get_real_savings. No explicit when/when-not instructions or alternative recommendations are provided.

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