flame_graph

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

No annotations provided, so the description carries the burden. It discloses interactivity ('click frames to zoom') and that it's a display/visualization tool (non-destructive read-like operation). However, it doesn't disclose whether simulated data is used by default (though the schema hints at this), what happens with invalid profile data, or any limitations of the visualization.

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?

Three sentences, zero waste. Efficiently conveys purpose, interaction model, and analytical value. Front-loaded with the core function and follows with interaction details.

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 visualization display tool with no output schema and no nested complexity, the description covers the essential behavior well. All three parameters are schema-documented. The interactivity and hot-path analysis disclosure give the agent enough to select and invoke it correctly. Minor gap: could state it doesn't modify anything, but this is low-risk for a visualization 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?

Schema coverage is 100% and all three parameters have descriptions. The description adds the note that profile uses simulated data if not provided (also in schema) and implies the title parameter. No parameter count is 0, so the description doesn't need to compensate heavily. It adds marginal insight (interaction behavior, hot path analysis) but doesn't enrich parameter understanding beyond the schema.

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?

Description says 'Display an interactive flame graph visualization for performance profiling' - clear verb+resource. Shows call hierarchy with execution time. It distinguishes itself from siblings (hello_world, list_sort, feature_flags, database_query) by the specific visualization type and profiling purpose, though it doesn't explicitly name a sibling alternative.

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?

Implies use in performance profiling context and mentions hot path analysis, but gives no explicit when-to-use or when-not-to-use guidance, no exclusions, and no mention of alternatives. The profiling context is implied but not stated as a requirement.

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