Initial Instructions

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

Annotations already declare readOnlyHint=true and destructiveHint=false, indicating a safe read operation. The description adds that it provides 'essential information' and is 'critical' to inform the agent, which adds context about importance. However, it doesn't specify format, length, or structure of the manual content beyond what annotations provide.

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 appropriately concise with two sentences that each serve distinct purposes: stating what the tool provides and giving critical usage instructions. It's front-loaded with the core purpose, though the second sentence could be slightly more streamlined.

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 has 0 parameters, annotations covering safety, and an output schema exists, the description provides adequate context about purpose and critical timing. It doesn't need to explain return values since output schema exists, but could optionally hint at manual content format for slightly better completeness.

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 discuss parameters since none exist, focusing instead on the tool's purpose and usage timing.

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 'provides the Serena Instructions Manual' which is a specific resource, though it doesn't specify the exact content or format of the manual. It distinguishes itself from siblings by being the only tool focused on providing essential instructions rather than performing project operations.

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 usage guidance: 'If you have not yet read the manual, call this tool immediately after you are given your task by the user, as it will critically inform you!' This clearly indicates when to use it (immediately after task assignment if manual not read) and implies it's foundational before using other tools.

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