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

With no annotations present, the description must carry the behavioral disclosure burden. It does so well by revealing a non-obvious behavior: 'transits are computed for the chart's as_of date ... not today unless the chart was created today.' It also discloses that houses are counted from BOTH the natal Moon and natal Lagna, which is a key behavioral trait beyond the schema.

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 well-structured with a clear opening, example use cases, and a separate IMPORTANT caveat about date semantics. It is slightly longer than strictly necessary, but every sentence adds valuable information and the key caveat is front-loaded enough to be noticed before invocation.

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 single-parameter tool with no output schema and no annotations, the description is quite complete: it explains what the tool computes, from which references, and how date behavior works. The main missing piece is any hint about the output format or fields returned, but this is less critical for a simple chart_id-based lookup and does not undermine correct selection or invocation.

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?

The input schema only documents chart_id as a required string, and schema description coverage is 0%, so the description needs to compensate. It adds some meaning by referring to 'the chart's as_of date' and directing users to create_chart, which implies chart_id identifies the natal chart of interest. However, it never explicitly describes chart_id itself, leaving part of the semantic burden on the parameter's self-evident name.

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 opens with 'Get gochara — where the planets are now relative to the natal chart', a specific verb+resource statement that clearly identifies the tool's function. It goes further by naming the two reference frames (Moon and Lagna) and listing concrete questions the tool answers, such as 'is Sade Sati running' and 'is Jupiter transiting well', which makes it easy to distinguish from sibling get_* tools.

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 clear usage context by listing example queries the tool is meant to answer ('is Sade Sati running', 'is today favourable'), which tells an agent when to invoke it. It also gives an important conditional about the as_of date and points to create_chart for other dates, but it does not explicitly name alternatives or state when not to use this tool.

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