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

Annotations already declare readOnlyHint=false, idempotentHint=false, openWorldHint=true and destructiveHint=false, so the write/open-world profile is covered. The description adds material context the annotations cannot: the exact credit cost (5,000, Tier 7), that it consumes roughly half a free monthly budget, and an explicit instruction to confirm with the user first. It still doesn't state the output medium (PDF vs HTML) or that repeated calls are billed again, so it stops short of a 5.

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?

Front-loaded with the payload contents in a single dense sentence, then a compact bracketed metadata block (group, endpoint, required, cost). No filler, no repetition of the title, and the most decision-relevant fact — the premium cost warning — is placed last with a warning marker where it will be noticed.

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?

An output schema exists, so return values need no explanation, and the cost/confirmation behavior is well covered. But for a premium, 5-parameter report tool sitting beside astroway_vedic_kundli and the astroway_reports_* family, the definition omits the one thing an agent most needs: how this differs from the plain Vedic kundli tool and what format it delivers. Adequate, but with a real routing gap.

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 description coverage is 60% and the schema itself carries rich per-field prose (timezone semantics, timezoneOffset hours, houseSystem letters, lat/lon rejection of short forms). The description contributes only '[Required: chart]' and the default 'Lahiri ayanamsa', which merely restates what the schema already documents. It adds no meaning for fields, precision, language, or whitelabel, so it sits at the baseline for partial coverage.

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 names a specific artifact (sidereal Vedic chart, Lahiri ayanamsa) and enumerates exactly what the deliverable contains: Lagna, Moon nakshatra/pada, all planet positions with nakshatra+pada+house, and a full 9-period Vimshottari Mahadasha tree. It is clear what the tool produces, but it never distinguishes itself from the sibling astroway_vedic_kundli, which by name covers the same subject matter — only the title's 'PDF or HTML' hints that this is the rendered report variant.

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 only usage guidance is the premium cost warning — '5,000 credits (Tier 7), ~50% of free monthly budget. Confirm with user before invoking' — which is genuinely useful pre-invocation advice. However, there is no routing guidance: nothing tells the agent when to pick this over astroway_vedic_kundli or the generic astroway_reports_generate. Usage context is implied by [Group: Reports] rather than stated.

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